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  • 1970-1974  (70)
  • 1965-1969  (24)
  • 1950-1954
  • 1920-1924
  • 1905-1909
  • 1860-1869
  • Kidney
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Langenbeck's archives of surgery 337 (1974), S. 883-883 
    ISSN: 1435-2451
    Keywords: Kidney ; Organ Preservation ; Transplantation ; Niere ; Organkonservierung ; Transplantation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Nierentransplantation ist eine wesentliche Ergänzung der Dauerdialysebehandlung geworden. In der Bundesrepublik Deutschland ist die Transplantationsfrequenz jedoch sehr niedrig. Dies ist enter anderem auf den Mangel an Spenderorganen zurückzuführen. Die Ausstellung hatte zum Ziel, die Methodik der Organentnahme und der Organkonservierung Bowie die notwendigen organisatorischen Maßnahmen aufzuzeigen. Die in der BRD aktiven Transplantationszentren wurden aufgeführt, um die Beteiligung anderer Kliniken an der Transplantationschirurgie anzuregen.
    Notes: Summary Kidney transplantation is an essential complement to chronic dialysis, but the frequency of transplantation is very low in the Federal Republic of Germany. One reason is the shortage of donor organs. The exhibition demonstrates the method of organ exstirpation and preservation of the organs as well as describing the necessary administrative measures: A list of the transplantation centres in the Federal Republic of Germany is given to encourage other clinics to become involved in kidney transplant operations.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Pediatric radiology 2 (1974), S. 39-41 
    ISSN: 1432-1998
    Keywords: Kidney ; blood flow ; circulation time ; reflux ; pyelonephritis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The intrarenal circulation time in rabbits was found to decrease when the intrapelvic pressure was elevated acutely. A possible explanation is a redistribution of the blood flow with part of the blood effectively by-passing some renal parenchyma and thereby hypothetically resulting in local ischaemia. At vesico-ureteral reflux the same mechanism may cause repeated episodes of ischaemia. This may well happen particularly in areas drained by a damaged papilla, where rises in the intra-pelvic pressure may be conducted directly into tubuli and peritubular capillaries and veins.
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  • 3
    ISSN: 1432-0827
    Keywords: Serum ; Calcium ; Phosphate ; Alkaline phosphatase ; Kidney
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract In 30 patients with chronic renal insufficiency (16 non-dialysed and 14 on dialysis) serum calcium, phosphate and alkaline phosphatase were determined and, in a crest biopsy specimen, morphometric determinations of bone qualities were calculated. A positive correlation was established between serum alkaline phosphatase, the osteoblast surface and the active resorption surface in both dialysed and non-dialysed patients. A positive correlation was also established between the osteoblast surface and the active resorption. In the non-dialysed patients a negative correlation was established between serum calcium and the osteoid surface.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 364 (1974), S. 365-369 
    ISSN: 1432-2307
    Keywords: Virus Diseases ; Cytomegalic Inclusion Disease ; Kidney ; Kidney Diseases ; Glomerulonephritis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This paper reviews a case of a newborn child which died soon after birth in consequence of a cytomegalic inclusion disease involving the brain, liver, lungs and kidneys. The interest of the case lies in the unusual finding of lesions of the vascular loops of the renal glomeruli. These lesions were represented by focal areas of homogeneous appearance which were strongly basophilic and PAS-positive. Although the nature of these areas has not been completely established, the renal lesions can be tentatively defined as focal, probably necrotizing glomerulonephritis. The association of this type of glomerular lesions with cytomegalic inclusion disease has not been previously reported.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Research in experimental medicine 162 (1974), S. 125-132 
    ISSN: 1433-8580
    Keywords: Kidney ; Concentrating mechanism ; Corticomedullary gradients ; Protein ; Niere ; Konzentrierung ; Corticomedulläre Gradienten ; Protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wurden die Albumingradienten der Rattenniere und ihre Beeinflussung durch Furosemid und hypertones Mannit nach mehrtägiger Infusion hyperosmolarer Natriumchloridlösungen untersucht. Als Indicator der Eiweißkonzentrationen diente der an Albumin gebundene Farbstoff Evans blue. Es wurde gefunden: 1. Nach mehrtägiger Natriumkonzentrierung (890 mOsm/l, Urinfluß 1,7 ml/Std) beträgt die Gesamtosmolarität im Gewebe der Papillenspitze 1015 ± 181 mOsm/l und im Sammelrohrurin 1059 ± 42 mOsm/l. Der Eiweißgradient nimmt von der Rinde zur Papillenspitze kontinuierlich auf das 4,25fache der Rindenwerte zu. 2. Nach Furosemid (2 × 0,7 mg/100 g KG) fällt die Gesamtosmolarität im Papillenspitzengewebe auf 344 ± 28 mOsm/l und im Sammelrohrurin auf 385 ± 30 mOsm/l ab. Das stündliche Harnvolumen erhöht sich auf 8,2 ± 2,04 ml. Die Albumine werden nur noch um das 1,8fache ihrer Rindenwerte und zu 35% ihrer ursprünglichen Konzentration angereichert. 3. Unter 20%iger Mannitinfusion (Flußgeschwindigkeit 1,5 ml/Std, Infusionszeit 110 min) fällt die Gesamtosmolarität im Papillenspitzengewebe auf 475 ± 84 mOsm pro Liter und im Sammelrohrurin auf 467 ± 51 mOsm/l ab. Das stündliche Harnvolumen wächst auf 6,4 ± 1,96 ml an. Die Albumine werden nur noch um das 2fache ihrer Rindenwerte und zu 42% ihrer Ausgangskonzentration angereichert. Für die Beeinflussung der corticomedullären Eiweißgradienten durch Mannit und Furosemid werden neben Änderungen der rheologischen Eigenschaften der Erythrocyten Volumen- und osmotisches Substanzangebot an die Vasa recta-Schleifen verantwortlich gemacht. Die Funktion dieser Gegenstromgefäße ist von der osmotischen Substanz- und Wasseraufnahme aus den Henleschen Schleifen und Sammelrohren abhängig.
    Notes: Summary Subject of the examinations were the albumin gradients of the tissue of the rat kidney and the influence of hypertonic mannitol and furosemide on it during long-term infusion of hyperosmolar sodium chloride. As an indicator of the protein concentrations Evans blue dye was injected, which binds to albumen. The following results were obtained: 1. After several days' sodium concentration (890 mOsm/l, urine flow 1.7 cc/hr) the total osmolarity in the tissue of the papillary tip is found to be 1015 ± 181 mOsm per litre and in the collecting ducts 1059 ± 42 mOsm/l. The protein gradients rise continuously towards the papillary tip up to 4.25 times of the cortex values. 2. After injection of furosemide (2 × 0.7 mg/100 g b.w.) the total osmolarity in the papillary tissue decreases to 344 ± 28 mOsm/l and in the collecting ducts to 385 ± 30 mOsm/l. The urine volume per hour increases to 8.2 ± 2.04 cc. Albumin is enriched merely to about 1.8 times of the cortex values and to 35% of its former concentration. 3. During the infusion of hypertonic mannitol (flow-rate 1.5 cc/hr, time of infusion 110 min) the total osmolarity of the papillary tissue decreases to 475 ± 84 mOsm/l and in the collecting ducts to 467 ± 51 mOsm/l. The urine volume rises to 6.4 ± 1.96 cc/hr. Albumin is enriched merely to about twice of the cortex values and to 42% of its original concentration. Besides changes of the rheological characteristics of the red cells, volume and osmotic substance supply to the vasa recta are held responsible for the influence of hypertonic mannitol and furosemide on the corticomedullary albumin gradients, while they are administrated. The countercurrent exchange efficiency of the vasa recta is dependent on both the water and osmotic substance uptake out of the loops of Henle and the collecting ducts.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Research in experimental medicine 162 (1974), S. 333-339 
    ISSN: 1433-8580
    Keywords: Kidney ; Concentrating mechanism ; Corticomedullary gradients ; Urea ; Electrolytes ; Niere ; Konzentrierung ; Corticomedulläre Gradienten ; Harnstoff ; Elektrolyte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An wachen, eiweißarm ernährten Wistar-Ratten wurde die Wirkung von Harnstoff auf die renale Wasserretention und Elektrolytkonzentrierung unter standardisierten Bedingungen (Trinkwasserentzug, mehrtägige kombinierte hypertone Harnstoff/NaCl-Infusion) untersucht. Die Ergebnisse lassen erkennen, daß Harnstoff aktiv aus den Sammelrohren resorbiert wird und daß Natrium bei Harnstoffzufuhr stärker im Nierenmarkgewebe angereichert wird als bei reiner Elektrolytinfusion. Die bei Harnstoffzufuhr erhöhten medullären Konzentrationen bewirken einen zunehmenden osmotischen Wasserentzug aus den Sammelrohren ins Interstitium. Die Harnvolumina nehmen bei Anstieg der Elektrolytkonzentrationen entsprechend ab. Es wird geschlossen, daß die wasserretinierende Wirkung des Harnstoffs am besten nachgewiesen werden kann, wenn — bei kalkulierter Wasser- und osmotischer Substanzzufuhr — die GFR konstant gehalten wird, weiterhin das Nephron hoch permeabel für Harnstoff ist, also bei maximalen medullären Natriumkonzentrationen und Harnstoff über längere Zeit bei gleichbleibender Konzentration infundiert wird.
    Notes: Summary Subject of the examinations was the special effect of urea to the renal water retention and electrolyte concentrating ability on protein lacking rats under standardized conditions (no drinking, long-term combined hypertonic urea/saline infusions). The results show, that urea is reabsorbed actively out of the collecting ducts and that sodium is better enriched in the renal medulla during simultaneous urea supply than with pure electrolyte infusion. These increased medullary concentrations cause an enlarged osmotic water removal out of the collecting ducts into the interstitium during urea supply so that the urine volumes decrease and the electrolytes are better concentrated in the urine. It is concluded, that the water retaining effect of urea could be proved best when the glomerular filtrates are kept unchanged, furthermore when the nephron is high permeable for urea, that is by maximal medullary sodium concentration, and when urea is infused by longterm supply in constant rations.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Research in experimental medicine 164 (1974), S. 19-33 
    ISSN: 1433-8580
    Keywords: Kidney ; Rat ; Ultrastructure ; Proximal tubule degeneration ; Heparinoid ; Niere ; Ratte ; Ultrastruktur ; Proximale Tubulusdegeneration ; Heparinoid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 24 Std nach i.v. Injektion von 100 mg/kg eines Pentosanschwefelsäureesters (SP 54) sind in der Nierenrinde von Ratten schwere degenerative Veränderungen der proximalen Tubuluszellen zu beobachten. Das Tubulusepithel ist flachkubisch umgewandelt, das Tubuluslumen ist angefüllt mit ausgestoßenen Mitochondrien und anderen Zelltrümmern. Am stärksten betroffen ist die Pars contorta des proximalen Tubulus. Weniger stark veränderte Tubuluszellen sind angefüllt mit Cytosomen, die eine spezifische Feinstruktur haben oder gehäuft gegenüber Kontrollen Cytoplasmaprotrusionen in das Tubuluslumen aufweisen. Die akute Tubulusdegeneration ist ein spezifischer Effekt von SP 54. Heparin bewirkt nur eine leichte Schwellung des Tubulusepithels, die häufiger auftritt als bei Kontrolltieren.
    Notes: Summary 24 hrs after the intravenous injection of 100 mg/kg of a Pentosansulfuricacidester (SP 54) severe degenerative alterations are observed in the proximal tubular cells in rat kidney cortex. The tubular epithelium has changed to a single layer of elongated cubic cells. The tubular lumen is filled with cellular debris and extruded mitochondria. The greatest change is seen in the pars contorta of the proximal tubule. Less degenerated tubular cells have a great number of cytosomes with a specific substructure or have cytoplasmatic protrusions into the tubular lumen. This acute tubular degeneration is a specific event after the administration of SP 54 and is not seen after an equimolar dosis of Heparin. Heparin induces only a slight swelling of the tubular epithelium, more frequent seen as in the control animals.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Pflügers Archiv 351 (1974), S. 323-330 
    ISSN: 1432-2013
    Keywords: Uricase ; Urate ; Allantoin ; Liver ; Kidney ; Microperfusion ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. In vivo uricase activity was tested in rats by injection of 2-C14 urate and measurement of the total C14 activity and the fractional activities of allantoin, allantoic acid and urea in samples of blood and urine. In control animals, 5 min after the injection, 70% of the plasma tracer was already present in the form of allantoin. No allantoic acid and urea were produced. Intestinectomy had no measurable influence on uricase activity. On the other hand, hepatectomy or ligation of the hepatic artery combined with subtotal viscerectomy did abolish uricase activity almost completely. 2. Following microinjections into proximal tubules of Ringer solution containing 2-C14 urate, urine samples during early recovery mainly contained labelled urate, whereas in later samples the fraction of labelled allantoin increased. About 12 min after the microinjection the urine of both kidneys contained equal amounts of tracer mainly in the form of allantoin. 3. When segments of proximal tubules were perfused with an equilibrium solution containing tracer amounts of C 14 urate, no urate was metabolized during its passage through the proximal tubule. 4. C 14 urate was offered from the peritubular capillaries and samples of tubular fluid were analyzed, Again, all the tracer in the tubular fluid was in the form of urate, indicating that urate is not oxidized when it is transported across the tubular cell. It is concluded from these results that: 1. The rat kidney has no significant uricase activity. 2. Urate transport in the kidney is not influenced by this enzyme. 3. The degradation of urate to allantoin takes place at extrarenal sites, mainly in the liver.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Pflügers Archiv 349 (1974), S. 183-190 
    ISSN: 1432-2013
    Keywords: Uric Acid Transport ; Hippurate Transport ; Organic Anions ; Kidney ; Liver
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Experiments were designed to determine whether renal excretion of uric acid is achieved by the same mechanism as for renal tubular excretion of hippurates and related organic acids. Surviving slices of rabbit kidney cortex were unable to accumulate C14-urate by a concentrative mechanism. Further, entry of C14-urate into renal slices was unaffected by acetate, probenecid or anoxia in accord with earlier observations from this laboratory with non-radioactive urate. Experience with isolated perfused rat liver supports the use of this experimental method as a model of the hippurate transport system. Unlike hippurate and a large number of related organic anions, neither urate nor C14-activity derived from urate was concentrated in the bile from this preparation. Probenecid did not inhibit excretion of the small amounts of C14-activity which did appear in the bile. Urate did not compete with indigo carmine, a nonmetabolizable substrate of the hippurate transport system, for excretion into the bile. From these findings, it is concluded that urate and organic acids such as hippurate do not behave similarly in kidney or in liver. The possibility that urate might be excreted by an independent active transport mechanism is not excluded. The demonstration that renal tissues can synthesize urate from hypoxanthine raises the possibility that urate synthesis might also occur in the intact animal and might contribute to the renal clearance of uric acid.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Pflügers Archiv 347 (1974), S. 223-234 
    ISSN: 1432-2013
    Keywords: Kidney ; Renal Blood Flow ; Acute Renal Failure ; Renal Resistance ; Clearance Techniques ; Renal Venous Outflow ; Temporary Ischemia of the Kidney
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Total renal blood flow (RBF-dir) and total renal resistance were determined in acutely uninephrectomized rats by measuring the renal venous outflow after catheterizing the renal vein. Renal vein catheterization and the procedure involved caused an initial fall in C-IN and C-PAH followed by a steady level over an experimental period of 2–3 h. Absolute and fractional water excretion increased approx. 9-fold during that time. Mean RBF-dir was 14.2±0.67 (N=13) ml/min×kg BW×1 kidney. In another series of animals acute renal damage was induced by subjecting the kidneys to a 60 min period of temporary ischemia 3 days prior to use. RBF-dir decreased 10%, total renal resistance increased 11%, neither parameter being significantly different from controls. The clearance of inulin and PAH, the extraction ratio of PAH, and the urine flow rate were depressed to about 10% of control (P〈0.001). A considerable discrepancy was found between data obtained by clearance methods and RBF-dir after ischemia: The ratio RPF-PAH/RPF-dir was 1.05 under control conditions and was significantly depressed to 0.47 (P〈0.005) after ischemia.—These results indicate that a general increase in resistance of the vasa afferentia alone cannot be responsible for the oliguric phase. At least two important factors are involved in the cause of oliguria 3 days after temporary ischemia: Backdiffusion of tubular fluid through the damaged tubular epithelium and a decrease in GFR.—Clearance methods are not considered to be reliable determinants of GFR and RPF in renal failure after temporary ischemia.
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Pflügers Archiv 352 (1974), S. 47-59 
    ISSN: 1432-2013
    Keywords: Kidney ; ATPase ; Transport ; Cortex ; Medulla ; Papilla
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The properties of microsomal ATPase were compared in the cortex, medulla and papilla of the rat kidney. 2. Activation of (Na+K)-dependent ATPase in the medulla was at lower potassium concentration than in the cortex or papilla. 3. (Na+K)-dependent ATPase in the papilla was more sensitive to ouabain than cortical or medullary ATPase. 4. (Na+K)-dependent ATPase in the kidney papilla was more sensitive to inhibition by calcium, cadmium andN-ethyl-maleimide than the enzyme from the kidney cortex or medulla. 5. Mg-ATPase in each region of the kidney was more resistant to inhibition by calcium, cadmium orN-ethyl-maleimide than the corresponding (Na+K)-dependent activity. 6. Mg-ATPase in the papilla was more resistant to inhibition by these inhibitors as well as by thiocyanate than the enzyme from cortex or medulla. 7. These data may suggest functional differences in the microsomal ATPase of various regions in the kidney.
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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Pflügers Archiv 349 (1974), S. 29-40 
    ISSN: 1432-2013
    Keywords: Kidney ; Tubular Reabsorption ; Tubular Maximum ; $$P_{CO_2 } $$ ; Plasma [HCO 3 − ]
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Renal reabsorption of bicarbonate was examined in Merino ewes. In all experiments the bicarbonate reabsorption was directly related to that of sodium. When the rate of bicarbonate reabsorption was expressed as the ratio of bicarbonate over sodium reabsorption, no tubular maximum for bicarbonate could be demonstrated. Arterial pH or $$P_{CO_2 } $$ did not affect the reabsorption of bicarbonate except through alterations in the plasma bicarbonate concentration. The ratio of bicarbonate over sodium reabsorption was directly proportional to the plasma concentration of bicarbonate over a wide range. This evidence suggests that the ionic reabsorption of bicarbonate constitutes a major part of total bicarbonate reabsorption. It does not, however, exclude a contribution from an active hydrogen ion secretory process, as the kinetic properteis of such a process are as yet undetermined.
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  • 13
    ISSN: 1432-2013
    Keywords: Paracellular Shunt Pathway ; Transtubular Permeability ; Perfused Toad Kidney ; Transtubular Osmotic Gradient ; Kidney ; Epithelia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Trace amounts of either labelled mannitol, sucrose, raffinose or inulin were added to the portal circulation in the doubly perfused toad kidney and their-urine-to-portal fluid, labelled molecules-to-chemical inulin ratio (denoted here asR) was evaluated. Under control isosmotic conditionsR was found to be inversely related to the probing molecule radius.R for inulin was practically zero.R for all probing molecules rose reversibly when the luminal fluid was rendered hyperosmotic by addition of 50 mmole mannitol to the aortic circulation, and even more so when 50 mmole urea was added per liter of aortic fluid. ThusR for raffinose rose from 0.0025±0.0002 (control) to 0.0126±0.0012 (+50 mM mannitol) and to 0.0967±0.0112 (+50 mM urea). This increase inR must be due to widening of the paracellular shunt pathway since the contribution of portal circulation to the glomerular filtrate was negligible and these molecules are known to stay extracellular. The present experiments suggest that transtubular urea (and osmotic) gradients may play a role in the regulation of the size of the paracellular shunt pathway.
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  • 14
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    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 283 (1974), S. 107-114 
    ISSN: 1432-1912
    Keywords: Kidney ; Adrenaline ; Catechol-O-methyltransferase (COMT) ; Inhibition ; H22/54 [(±)-α-Dihydroxyphenyl]-n-valeramid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In the dog kidney catecholamines are O-methylated before being secreted by the tubule (Hempel et al., 1973). Adrenaline was used in an investigation to determine whether or not O-methylation is a prerequisite for the tubular secretion of a catecholamine in the dog. In dogs (n=3) treated with the COMT inhibitor H22/54 [(±)-α-(3,4-dihydroxyphenyl)-n-valeramid] the excretion of 14C-(±)-adrenaline and the pattern 14C-adrenaline metabolites in urine were measured. 14C-adrenaline (9.2 μg per injection) was injected simultaneously with 3H-inulin into both renal arteries. Eigth injections of radioactive material were given to each animal. COMT was inhibited before the second 14C-adrenaline injection by infusion of H22/54 into the left renal artery in doses of 0.16, 0.72 and 3.2 mg/kg b.w., respectively. Without H22/54 the injected dose of 14C-adrenaline was excreted by the kidney within 12 min as followed: 22.2 ± 6.0% (n=6) as 14C-adrenaline, 21.8 ± 7.0% (n=7) as 14C-metanephrine, and 9.3 ± 2.2% (n=7) as deaminated or conjugated 14C-adrenaline metabolites. H22/54 reduced the excretion of 14C-metanephrine to 9–28.2% of the control value, whereas the 14C-adrenaline excretion was considerably increased, up to 200% of the control. It is concluded that the additional 14C-adrenaline observed in urine after COMT inhibition was secreted by the tubule. Thus, O-methylation seems not to be a prerequisite for tubular secretion of adrenaline in the dog.
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  • 15
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    Cell & tissue research 147 (1974), S. 183-190 
    ISSN: 1432-0878
    Keywords: Kidney ; Rat ; Bowman's capsule ; Experimental hypertension
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The parietal layer of Bowman's capsule was examined in the rat in control animals and in animals made hypertensive by treatment with desoxycorticosterone acetatesaline and by clipping of the renal artery. At an early stage of elevation of blood pressure and, occasionally, prior to elevation of blood pressure, the epithelial cells of this layer showed basal cytoplasmic protrusion and reduplication accompanied by an increase in the thickness of the basement membrane. These changes preceded evidence of glomerular or renal arteriolar pathology. They presumably reflect either a response of this layer to increased blood pressure and modified glomerular function, or a direct effect of the factors that also induces blood pressure elevation. In either case, they imply a greater functional significance for the parietal layer than has usually been attributed to it.
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  • 16
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    Cell & tissue research 148 (1974), S. 417-429 
    ISSN: 1432-0878
    Keywords: Kidney ; Sexual segment ; Natrix natrix ; Histochemistry ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The sexual segment of the kidney of Natrix natrix has been investigated cytochemically, light microscopically and ultrastructurally. The sexual segment, which seems to be an important accessory sexual organ, has a single layer of a columnar epithelium. The epithelial cells are filled with large secretion granules of a wide range of electron densities. Cytochemical reactions for neutral and acid mucosubstances are negative, but the cells show a strong positive staining for phospholipids. Within the cells of the sexual segment we have localised by histochemical means several hydrolases and oxydoreductases, which reflect enzyme activities of the glycolytic pathway, the citrate cycle, and related metabolic pathways. The activities of the hydrolytic enzymes acid phosphatase, acetylcholinesterase and indoxylacetate esterase are remarkably high within the epithelial cells. Furthermore it was found that the sexual segment tubules possess contractile elements which extends over the basal surface of the epithelial cells. These contractile cells exhibit a very high activity of alkaline phosphatase. Single unmyelinated axons are located between the contractile elements and the basal lamina of the sexual segment cells. The functional significance of the sexual segment structures is briefly discussed.
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  • 17
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    Naunyn-Schmiedeberg's archives of pharmacology 277 (1973), S. 373-386 
    ISSN: 1432-1912
    Keywords: Kidney ; Renal Handling ; Dopamine ; Noradrenaline ; Adrenaline ; Catechol-O-Methyl-Transferase (COMT)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In 12 female dogs renal excretion and catabolism of 14C-(±)-adrenaline, 14C-(±)-noradrenaline, 14C-dopamine and 3H-(±)-normetanephrine were investigated using a modified stop-flow technique. Radioactive compounds were infused, together with inulin, into the left renal artery for 10 min. During the first 2 min of the infusion period the left ureter was occluded. Urine samples were serially collected from both kidneys up to the end of the infusion. In the urine the total radioactivity and the pattern of radioactive metabolites were measured. On average, the infused kidney excreted from the infused dose of 14C-adrenaline 9.4% as adrenaline, 27.9% as metanephrine and 5.8% as deaminated or conjugated metabolites. From infused 14C-noradrenaline 7.4% was excreted as noradrenaline, 3.5% as normetanephrine and 1% as deaminated or conjugated compounds. When 3H-normetanephrine was infused the urine contained only radioactive normetanephrine (22.2%). From the infused dose of 14C-dopamine 9.6% was excreted as dopamine, 16.2% as 3-O-methyldopamine and 3.7% as deaminated or conjugated compounds. — Urine from the other kidney contained 1/25 to 1/5 the radioactivity of that from the infused side, but the pattern of radioactive compounds was similar. From the excretion rate of simultaneously infused inulin the filtration fraction of the infused kidney was determined. That part of the infused 14C-catecholamines which was excreted unmetabolized in the urine, corresponds to the filtration fraction in this kidney. Therefore, it is suggested, that in mammals the unmetabolized catecholamines of the urine are mainly excreted by glomerular filtration and not by tubular secretion. On the other hand, the urinary O-methylated radioactive catecholamines, which were excreted by the infused kidney at a high rate, were formed in this organ from the infused catecholamines and were excreted by tubular secretion. Thus, in mammals tubular secretion is linked to an inactivation of these compounds by O-methylation.
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  • 18
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    Research in experimental medicine 161 (1973), S. 21-29 
    ISSN: 1433-8580
    Keywords: Amiloride ; Autoradiography ; Kidney ; Potassium-saving Diuretics ; Amilorid ; Autoradiographie ; Niere ; Kaliumsparende Diuretica
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Nierenaufnahme und intrarenale Verteilung von14C-Amilorid wurde nach intramuskulärer Injektion an Mäusen untersucht. 30 min nach der Injektion von 0,5–5 mg Amilorid/kg wurden Aktivitäten gemessen, die einer renalen Konzentration von 30–650 ng Amilorid/g Niere entsprechen. Der Quotient Nierenaktivität/Plasmaaktivität lag dabei zwischen 13:1 und 20:1. Anzeichen für eine Sättigung der renalen Amiloridanreicherung waren bis zu einer Dosis von 5 mg Amilorid/kg nicht zu beobachten. Mit Hilfe der Gefrierschnittautoradiographie wurde festgestellt, daß14C-Amilorid sich nach intramuskulärer Injektion vor allem im terminalen Hauptstück des Außenstreifens und im Sammelrohrlumen anreichert. Da die gleiche intrarenale Verteilung nicht nur bei anderen, im proximalen Tubulus sezernierten organischen Basen wie z. B. Histamin, sondern auch bei den sezernierten organischen Säuren wie PAH, Phenolrot, Diodrast und Furosemid vorkommt, wird für solche Bilder die Bezeichnung „proximal-sekretorisches Verteilungsmuster“ vorgeschlagen. An Hand seiner intrarenalen Verteilung werden mögliche Zusammenhänge zwischen dem Wirkungsort, dem vermuteten Wirkungsmechanismus und der Konzentration von Amilorid entlang des Nephrons diskutiert.
    Notes: Summary The renal uptake and intrarenal distribution of14C-Amiloride was studied after intramuscular injection in mice. 30 min after injection of 0.5–5.0 mg Amiloride/kg body weight, renal activities were found corresponding to 30–650 ng Amiloride/g kidney. The ratio of renal/plasma activity ranged between 13:1 and 20:1. Neither renal concentration nor this ratio reached saturation levels with doses up to 5.0 mg Amiloride/kg body weight. Cryostat section autoradiography showed high14C-Amiloride-concentrations mainly in the terminal portion of the proximal tubule (in the outer stripe of the outer medulla) and in the lumen of the collecting ducts. As identical distribution patterns have been found for other organic bases secreted in the proximal tubule (e.g. histamine) and organic acids (e.g. PAH, phenol red, Diodrast and Furosemide) the term “proximal secretory distribution pattern” for this type of radiographic image is proposed. Correlations between the mechanism and locus of action and the concentration of Amiloride in the divers segments of the nephron are discussed on the basis of the intrarenal distribution pattern.
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  • 19
    ISSN: 1433-8580
    Keywords: Organ preservation ; Kidney ; Organ damage ; Hypothermia ; Perfusion ; Nuclear medicine ; Organkonservierung ; Niere ; Organschädigung ; Hypothermie ; Perfusion ; Nuclearmedizin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Funktionstüchtige und experimentell geschädigte Hundenieren wurden zur Konservierung im Belzer-Gerät hypotherm perfundiert. Die Beurteilung des Organzustandes erfolgte mit herkömmlichen Methoden (Druck/Flow-Relation, Organgewicht, Replantationsergebnis). Gleichzeitig wurden nuclearmedizinische Verfahren erprobt, mit dem Ziel, zu jeder Zeit der Konservierungsphase definitiven Aufschluß über die nach Replantation zu erwartende Funktionstüchtigkeit des Organs zu erhalten. Mit Hilfe von J131-o-Hippursäure konnte gezeigt werden, daß die Tubulusfunktion bei 5°C ruht und unter Hypothermiebedingungen nicht als Gradmesser für den Organzustand in Betracht kommt. Demgegenüber erwies sich ein sequenzszintigraphisches Verfahren als brauchbar, bei dem der In113m-EDTA-Durchsatz durch die Niere mit Hilfe eines Szintillationskamera-Computersystems bestimmt wurde. Aus Zeit-Aktivitäts-Verläufen ermittelte Parameter gaben im gesamten Konservierungsverlauf zuverlässig Aufschluß darüber, ob ein Organ intakt bzw. mehr oder weniger geschädigt war.
    Notes: Summary Uninjured as well as experimentally damaged kidneys of dogs were preserved by hypothermic perfusion according to the method of Belzer. The functional conditions of the organs were estimated by conventional methods. At the same time nuclear medical procedures have been tried in order to get more reliable information about the probable degree of organ damage at any time of the preservation phase. By means of J131-Hippurate it could be established that renal tubuli are not working at a temperature of 5°C. Therefore, Hippurate clearance can not be used as a criterion of the functional state under hypothermic conditions. Contrary to this finding the manner of transit of In113m-EDTA through the kidney yielded useful parameters for valuation of the organ. For the present investigations a Scintillation Camera-Computer System has been used which can, for routine purposes, be substituted by a simple scintillometer-recorder system.
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  • 20
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    Naunyn-Schmiedeberg's archives of pharmacology 280 (1973), S. 161-176 
    ISSN: 1432-1912
    Keywords: Protease Inhibitor ; Peptides ; Kidney ; Absorption ; Brush Border
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A brush border membrane fraction from rat renal cortex binds the polyvalent protease inhibitor (Trasylol®) from bovine organs. Saturation is complete in the presence of about 40 nanomoles/ml of protease inhibitor. The maximal binding capacity is about 18 nanomoles (or 117 μg) of protease inhibitor per mg of brush border membrane protein. The affinity constant, as calculated from the double reciprocal plot of binding, is 7 μM. Removal of the microvillar knobs by incubation with papain does not change the binding characteristics, whereas incubation of the brush border with sialidase markedly decreases the fixation of the peptide. Guanidination fails to alter the binding properties, whereas the tetramaleoyl derivative is not fixed at all. Therefore, the positive net charge of the peptide seems to play an important role. Insulin, glucagon and bradykinin interact with the brush border fraction in a manner entirely different from that of the protease inhibitor. Over a wide concentration range, about 6 to 10% of these peptides are bound independent of the concentrations added. Our present and previous results suggest that binding to the brush border membrane is the initial step in the pinocytotic reabsorption of the protease inhibitor and possibly of other peptides too. The tremendous concentration of the protease inhibitor by the kidney cortex is assumed to be due to its high affinity to the brush border membrane in vivo.
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  • 21
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    Naunyn-Schmiedeberg's archives of pharmacology 280 (1973), S. 209-216 
    ISSN: 1432-1912
    Keywords: Gluconeogenesis ; Kidney ; N-Monomethylacetamide ; Acidosis ; Glutamine Metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Kidney cortex slices from rats poisoned with the diabetogenic drug N-monomethylacetamide (NMMAA) produced substantially more glucose from exogenous α-ketoglutarate (α-KG) than did slices from controls. The stimulation of gluconeogenesis was not due to enhancement of renal phosphoenolpyruvate carboxykinase activity, which was found to be similar in experimental and control rats. Despite acceleration of α-KG conversion to glucose, gluconeogenesis from glutamine was not stimulated. The gluconeogenic flux from α-KG, thus, was not rate-limiting for glutamine conversion into glucose. However, when the pH of incubation medium was lowered from 7.5 to 7.2, the rate of gluconeogenesis from glutamine increased together with that from α-KG in slices from both normal and poisoned rats. The data demonstrate major difference in the mechanism of stimulation of renal gluconeogenesis by NMMAA poisoning and by acidosis.
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  • 22
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    Pediatric radiology 1 (1973), S. 172-177 
    ISSN: 1432-1998
    Keywords: Kidney ; amyloidosis ; nephrotic syndrome ; familial Mediterranean fever
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Radiological changes in the intravenous pyelogram of 36 children with renal amyloidosis secondary to familial Mediterranean fever have been evaluated. Renal enlargement was consistently found. In the majority of the patients there was also a narrow rigid appearance of the ureters. The combination of these two radiographic findings appear to be virtually diagnostic of renal amyloidosis.
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  • 23
    ISSN: 1432-2013
    Keywords: Antihypertensive Agents ; Desoxycorticosterone ; Kidney ; Nephrectomy ; Renin ; Sodium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In rats made hypertensive by partial constriction of one renal artery and contralateral nephrectomy, large doses of furosemide had no hypotensive effect. However, when furosemide natriuresis was followed by removal of the clamped kidney, arterial blood pressure was greatly reduced. The fall of blood pressure induced in this manner was significantly correlated with the amount of sodium and water lost. The absence of a hypotensive effect of furosemide in rats with one-kidney Goldblatt hypertension appeared to be due to enhanced renin secretion. Furosemide not followed by nephrectomy caused a fall of blood pressure in rats with one-kidney Goldblatt hypertension after renin-depletion by desoxycorticosterone and salt treatment. Sodium wastage induced by peritoneal dialysis after removing the clamped kidney also lowered the blood pressure of hypertensive rats.
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  • 24
    ISSN: 1432-2013
    Keywords: Kidney ; Microcirculation ; Renal Blood Flow ; Acute Renal Failure ; Intravital High-Speed Microcinematography ; Peritubular Capillaries ; Welling Points
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The incident-light, high-frequency microcinematography of the kidney surface of rats is described as a new method for investigating renal microcirculation. The welling point area served as the anatomical reference point for microcirculatory measurements. In the first section of vessel distal to the welling point the average flow velocity was 2.32±0.24 mm/sec; the diameter was 15.91±0.92 microns. Flow rate in the efferent arteriole, calculated from the flow rate in the first vessel section distal to the welling point and the degree of ramification, was 103 nl/min. The results closely agree with total renal blood flow that was determined simultaneously. As an example for measurements taken under different conditions, a model for experimental acute renal failure was chosen. In kidneys subjected to a 60 min period of ischemia three days prior to use, the peritubular blood flow at the kidney surface was decreased only by 1/4; the difference in the means was insignificant. Therefore, a lasting cortical ischemia cannot be the only cause for the persistent oliguria in experimental acute renal failure.
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  • 25
    ISSN: 1432-2013
    Keywords: l-Histidine Transport ; Proximal Tubule ; Transport Kinetics ; Fanconi Syndrome ; Kidney ; Microperfusion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The kinetics ofl-histidine reabsorption by the proximal convolution of the rat nephron have been studied by stationary microperfusion with simultaneous perfusion of peritubular capillaries. Steady-state concentrations (C ∞) and transepithelial concentration differences (Δc ∞) were determined over a wide range of peritubular bistidine concentrations. It was found that Δc ∞ increased hyperbolically with increase in luminal and peritubular histidine concentrations suggesting saturation transport kinetics. Furthermore Δc ∞ declined linearly along the convolution suggesting that nett active transport was not constant throughout the tubule. Using an expression to describe the rate of attainment of steady-state concentration in terms of lummal and peritubular histidine concentrations, histidine permeability coefficient (P), the maximum rate of active histidine transport (J max) and the half saturation constant of the transport reaction (K m ), we were able to determine the cause of the tubule inhomogeneity. We find thatP (14.1×10−5 cm/s) andJ max (45×10−10 mol/cm2· s) are constant along the convolution but thatK m increases markedly from about 5.4 mmol/kg 26% of the way along the convolution to 40 mmol/kg at 86%. These findings suggest that the histidine reabsorptive mechanism would be relatively inefficient with histidinuria occurring at all plasma concentrations but it would have enormous reserve capacity so that saturation would not readily occur. This prediction accords with available data on histidine clearance in the rat.
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  • 26
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    Pflügers Archiv 345 (1973), S. 81-92 
    ISSN: 1432-2013
    Keywords: Urea ; Sodium ; Kidney ; Transport ; (Na+K)-ATPase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Microsomal ATPase activity was studied in three regions of the rat kidney: cortex, medulla and papilla. (Na+K)-ATPase activity was highest in the medulla but a substantial activity, comparable to that in the cortex, was also present in the papilla. In the presence of high sodium (200–320 mM) or urea (100–900 mM) progressive inhibition of Mg-ATPase activity was observed in all three regions of the kidney. Urea (900 mM) or Na (320 mM) caused activation of (Na+K)-dependent ATPase in the medulla and inhibition of this enzymatic activity in the papilla of the kidney. Total microsomal ATPase activity in the medulla was unchanged in the presence of urea or sodium but was reduced in the papilla. Urea inhibited non-selectively Mg-p-nitrophenylphosphatase and K-activated p-nitrophenylphosphatase in all three parts of the kidney. These findings may point to a molecular basis for the function of urea and of sodium in the concentrating mechanism of the kidney.
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  • 27
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    Pflügers Archiv 343 (1973), S. 267-272 
    ISSN: 1432-2013
    Keywords: Kidney ; Lanthanum ; Tight Junctions ; Epithelia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The penetration of either “ionic” or “colloidal” lanthanum into the tight junctions of different tubular segments of the rat kidney was studied with the electron microscope. After perfusing the tracer through the aorta it was found that “ionic” and “colloidal” lanthanum penetrated the tight junctions of both the proximal and distal convoluted tubules, while the junctions of the collecting tubules were free of tracer. An attempt to correlate junctional tightness and electrical resistance in these epithelia is presented.
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  • 28
    ISSN: 1432-2013
    Keywords: Saline Infusion ; Ultrafiltrable Calcium ; Parathyroid Gland Activity ; Ultrastructure of the Rat Parathyroids ; Kidney
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Experiments have been performed in adult female rats to examine the effects of saline infusion on calcium concentration in plasma ultrafiltrate and on the ultrastructure of the parathyroids as studied with the electron microscope. Intravenous infusions of isotonic saline of at least 10 ml within 30 min decreased calcium concentration in plasma ultrafiltrate from 3.04±0.15 mEq/l to 2.79±0.11 eEq/l (P〈0.001). Saline infusions of 2 h duration at a rate of 0.5 ml/min decreased significantly the number of secretory granules in the parathyroid cells and induced considerable growth of the Golgi apparatus. It is concluded, that saline infusions in the rat decrease the ionized fraction of plasma calcium concentration thereby increasing parathormone secretion rate.
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  • 29
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    Cell & tissue research 138 (1973), S. 545-555 
    ISSN: 1432-0878
    Keywords: Kidney ; Bufo bufo ; Juxtaglomerular apparatus ; Macula densa ; Light Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In a light microscopic study the course of the tubule in the kidney of the toadBufo bufo was studied. The distal tubule returning to the glomerulus of its origin appears to enclose the afferent arteriole. In that area, from which a three dimensional graphic reconstruction is made, there is an intimate contact between tubular and vascular wall. The latter contains granulated media cells. In the part of the tubule adjacent to the afferent arteriole an accumulation of nuclei is present. It is suggested that this structure is similar to the macula densa of the mammalian juxtaglomerular apparatus. The functional significance of a stricture in the tubule distally from the macula densa-like structure is discussed.
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  • 30
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    Cell & tissue research 136 (1973), S. 479-499 
    ISSN: 1432-0878
    Keywords: Kidney ; Male rat ; Proximal tubule segments ; Electron microscopy, cytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pars descendens (pars recta) of the proximal tubule in the male rat kidney, consisting of the terminal part of the second proximal segment (P2) and of the third proximal segment (P3), was studied with the electron microscope. A technique of tissue orientation and trimming was used which permitted precise topographic definition of the tubules studied in the electron microscope. The terminal descending part of the P2 showed some minor differences from the convoluted part of this segment, and ultrastructure also changed along the course of the P3. In the beginning of the latter segment numerous, shallow interdigitations were observed between adjacent cells; along the course of the segment they decreased in number or disappeared. In the initial part of the P3 mitochondria were more abundant than in the terminal portion of the segment and at least as numerous as in the straight part of the P2. Also, the dense, acid phosphatase-positive cytoplasmic bodies decreased somewhat in size along the course of the P3. The smooth surfaced endoplasmic reticulum reached a higher development in the P3 than anywhere else in the proximal tubules.
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  • 31
    ISSN: 1432-0878
    Keywords: Kidney ; Sexual accessory organs ; Reptiles ; Secretion ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Kidneys of adult male and female lizards were studied by electron microscopy, in order to understand the ultrastructure of the collecting duct and a differentiated part thereof, the sexual segment, which is an important accessory sexual organ. First portion of sexual segment in males: The cells are filled with large secretory granules of a wide range of opacities. The granular endoplasmic reticulum is abundant; basal formations of superimposed flat cisternae are frequent. Distended vesicles and microvesicles prevail in the supranuclear, well developed Golgi apparatus. Evidences indicate that secretion of these cells is holocrine. Second portion of sexual segment in males: All of the secretory granules are apical in location and relatively electron-opaque; they show a denser core. This core is formed by a substance which, after lying in contact with ribosomes, enters the secretory vesicles of the highly developed Golgi apparatus. A lighter substance is then condensed around it. The secretion of the granules is merocrine. The granular endoplasmic reticulum is very abundant in these cells, but basal ergastoplasmic formations are lacking. Sexual segment in females: The cells show features similar to those of the male first portion, but they are smaller. Undifferentiated collecting duct: Most of the cells are mucigenic. They have small ovoid, apical secretory granules. The density of the granules varies from cell to cell; when they are electron-lucent, they exhibit laminar or dotted opaque figures. Moderately developed Golgi apparatus and granular endoplasmic reticulum, as well as elongated mitochondria, occur in mucigenic cells. Intercalated among the latter are non-secretory cells. They have very abundant mitochondria, numerous microvilli, many pinocytic and smooth-membrane vesicles, whereas the organelles participating in synthetic processes are poorly developed; their function is most likely related to active solute transport.
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  • 32
    ISSN: 1432-0878
    Keywords: Juxtaglomerular cells ; Kidney ; Teleost (Gasterosteus) ; Migration ; Kidney structure ; Morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The renal corpuscles, juxtaglomerular cells, nephronic tubules, and ureters of female sticklebacks were studied. In fresh water fishes, the diameter of the renal corpuscles is similar to that found in fishes obtained from the sea, whereas the diameter of the glomeruli and the nuclei of the podocytes are slightly larger. Furthermore, in fresh water the podocytes produce secretory globules, which show some of the histochemical characteristics of the substance constituting the glomerular basement membrane. In sea water animals, secretory phenomena are absent. Mesangial cells, which are scarce in fresh water fishes, are numerous in marine animals. Similarly, juxtaglomerular cells, hard to find in fresh water fishes, are prominent in specimens from the sea. The development of the epithelia of the nephronic tubules and of the ureters is better in fresh water. The cells and the nuclei are larger. In the first proximal tubule, which is involved in the reabsorption and the digestion—by lysosomes—of macromolecules, “micropinocytosis vermiformis” occurs. The results of stereological analysis of the fractional volume of the mitochondria and of the relative extent of the infoldings of the basal cell membranes—the location of the ion transport mechanisms—in the three different segments of the nephronic tubule and in the ureter, point to the existence of a structural gradient along the kidney tubules. In fresh water fishes the mitochondrial volume, per surface unit of basal cell membrane, is low in the first proximal segment and is increasingly higher in the other segments, while the highest value is found in the ureter. This structural gradient may be functionally linked with osmotic and ionic gradients, which exist in the renal tubules in fresh water. In the kidney tubules of marine sticklebacks, which do not show a major osmotic gradient, the structural gradient is small. The results are discussed on the basis of the known physiological differences in the function of the kidney of euryhaline teleosts in fresh water and in the sea.
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  • 33
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    Cell & tissue research 140 (1973), S. 101-124 
    ISSN: 1432-0878
    Keywords: Kidney ; Contractile structures ; Embryonic metanephros ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cytoplasmic filaments have been observed in the cells of normal and pathological kidneys. These filaments are usually grouped into bundles anchored to electron dense bodies underlying the cell membrane. In the embryonic human metanephros the filaments are found within the cells of different portions of the nephron at various stages of development. They appear first in the podocytes, almost simultaneously in the Bowman's capsule and tubular cells, then in the “mesangial cells”, and finally in the cells of the media of the afferent glomerular and interlobular arterioles. The presence of filaments and their attachment bodies in the mammalian nephron suggests that the podocytes and the so-called mesangial cells have a contractile activity, thus representing an intraglomerular apparatus which regulates the intravascular pressure, blood flow and filtration rate in the glomerular capillaries, whilst the contractile activity of the Bowman's capsule and proximal, distal, and collecting tubules, could facilitate the progression of the filtrate. The increase in number of the filaments in some pathological conditions is probably related to the functional changes of the intraluminal pressure in the glomerular capillaries, in the Bowman's space, and in the tubular lumen.
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  • 34
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    Medical & biological engineering & computing 11 (1973), S. 310-318 
    ISSN: 1741-0444
    Keywords: Kidney ; simulation ; analogue ; water reabsorption
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Description / Table of Contents: Sommaire Cette communication décrit une simulation de calcul analogique du contrôle de l'osmolalité du sang au moyen du transfert d'eau à partir du tubule cortical et du tube collecteur, à travers la région médullaire, jusqu'aux vaisseaux droits. Quand la simulation est sujette aux tests séparés d'ingestion d'eau et d'injection de saline, elle produit des résultats réalistes, quand on les compare aux enregistrements de tests semblables sur l'homme et sur les animaux expérimentaux. Pour parvenir à un fonctionnement général satisfaisant de la simulation, il a été nécessaire d'inclure des facteurs qui soient compatibles avec un rôle double pour l'h.a.d. Dans le modèle, l'effect de l'h.a.d. n'est pas seulement de changer la perméabilité de l'épithélium tubulaire, mais aussi d'altérer la vitesse de l'afflux du sang et la pression hydrostatique dans les vaisseaux droits.
    Abstract: Zusammenfassung Dieser Aufsatz beschreibt die Simulation durch einen Analog Computer der Kontrolle von Blutosmolalität, mit Hilfe der Wasserübertragung von dem distal tubulus und Sammelgang durch das Mark zum vasa recta. Diese Simulation, wenn sie getrennten Testen von Wassereinnahme und Salzinjektion unterzogen ist, bringt realistische Resultate wenn man sie mit den Ergebnissen ähnlicher Versuche an Menschen oder Versuchstieren vergleicht. Um eine in allen Punkten befriedigende Simulation zu bekommen, war es notwendig, Faktoren einzubeziehen, die mit einer Doppelrolle für a.d.h. übereinstimmen. In dem Modell ist der Effekt von a.d.h. nicht nur dazu da, um die Durchlässigkeit des tubular epithelium zu ändern, sondern er verändert auch die Blutströmungsge-schwindigkeit und den hydrostatischen Druck in der vasa recta.
    Notes: Abstract This paper describes an analogue-computer simulation of the control of blood osmolality by means of water transfer from the distal tubule and collecting duct through the medulla to the vasa recta. The simulation, when subject to the separate tests of water ingestion and saline injection, produces realistic results when compared with the records of similar tests on humans and on experimental animals. To achieve the satisfactory overall performance from the simulation, it was necessary to include factors which are consistent with a dual role for a.d.h. In the model, the effect of a.d.h is not only to change the permeability of the tubular epithelium, but also to alter the blood-flow rate and hydrostatic pressure in the vasa recta.
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  • 35
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    Research in experimental medicine 158 (1972), S. 171-179 
    ISSN: 1433-8580
    Keywords: Kidney ; Concentrating Mechanism ; Corticomedullary Gradients ; Protein ; Niere ; Konzentrierung ; Corticomedulläre Gradienten ; Protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Nach chronischer Infusion hypertoner Natriumchlorid- bzw. Harnstofflösungen wurden die Eiweißgradienten im Gewebe der Rattenniere im wachen Zustand und während Narkose ermittelt. Als Indicator der Eiweißkonzentrationen diente der an Albumin gebundene Farbstoff Evans blue. Die Farbstoffkonzentration der unterschiedlichen Nierengewebsregionen ließ demnach Rückschlüsse auf die Verteilung der intravasalen und mobilen Albumine im Markgewebe zu. Die Untersuchungen zeigen eine Zunahme der Albuminkonzentrationen von der Nierenrinde bis zur Papillenspitze, wobei ein Maximum des Anstiegs bei NaCl-Belastung im wachen Zustand und in Narkose erreicht wird. Die Erklärung dieser Befunde wird in dem unterschiedlichen Verhalten der Einzelfiltratbildung der corticalen und juxtamedullären Nephrone gesehen. Für Änderungen der Eiweißkonzentrationen unter Narkosebedingungen wird eine vermehrte Wasserrückresorption durch Adiuretin-Sekretionsstimulierung verantwortlich gemacht.
    Notes: Summary The protein gradients of the tissue of the rat kidney were obtained during chronic infusion of hypertonic sodium chloride and urea solutions, both with and without the administration of anesthetic. As an indication of the protein concentrations Evans blue dye was injected, which binds to albumen. From the concentration of dye in the various tissue regions of the kidney conclusions were drawn concerning the distribution of intravascular and mobile albumen in tissue. The experiments showed an increase in the albumen concentrations from the cortex to the papillary tip, the greatest increase being obtained with NaCl solutions whilst the animals were awake or under anesthetic. These findings can be attributed to a difference in behaviour between cortical and juxtamedullary nephrones in the formation of individual filtrates. Enlarged reabsorption of water by a stimulation of ADH were held responsible for changes in the protein gradients during anesthetic.
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  • 36
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    Anatomy and embryology 138 (1972), S. 99-109 
    ISSN: 1432-0568
    Keywords: Human embryo ; Urinary system ; Kidney ; Bladder ; Developmental stages
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A documented scheme of the early development of the human urinary system is presented. It is based on (1) reports of workers who personally studied staged embryos, and (2) personal observations and confirmations. The necessity of studying staged embryos in order to determine the precise sequence of developmental events is stressed.
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  • 37
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    Acta neuropathologica 20 (1972), S. 217-224 
    ISSN: 1432-0533
    Keywords: Aspartylglucosaminuria ; Enzymes ; Brain ; Liver ; Kidney
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Brain, liver, kidney and spleen biopsy and autopsy specimens were taken from patients with aspartylglucosaminuria for biochemical investigations. Total cholesterol values for brain and liver were normal as were also the values for N-acetylneuraminic acid in brain. Lipid phosphate was slightly increased both in the brain and liver. The thin-layer chromatographic patterns of brain gangliosides and phospholipids were normal. In the group of fourteen different lysosomal enzymes the activity of N-aspartyl-β-glucosaminidase was markedly decreased in the brain, liver and spleen but not in the kidney. The activities of a number of other enzymes, especially those of N-acetyl-β-d-glucosaminidase and N-acetyl-β-d-galactosaminidase were high in the same three tissues and again normal in the kidney. No consistent abnormalities were recorded in the groups of three microsomal and three other enzymes. The biochemical findings seem to be characteristic to aspartylglucosaminuria and delineate it as a special disease entity.
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  • 38
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    Acta neuropathologica 20 (1972), S. 207-216 
    ISSN: 1432-0533
    Keywords: Aspartylglucosaminuria ; Lysosomes ; Liver ; Kidney ; Brain
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Liver, kidney and brain biopsies were taken from patients with aspartylglucos-aminuria for electron microscopic studies. Abnormally large lysosomes were observed in all tissue specimens. In the liver, they appeared even larger than the nucleus of the same cell and were limited with a single membrane. They were most prominent in the parenchymal cells, contained finely granular, electron lucent material, and were most abundant near the bile canaliculi. Smaller lysosomes, containing electron dense material, were also observed. Rough and smooth endoplasmic reticulum were highly dilated, glycogen particles were absent, and the Golgi apparatus was always very small. In the kidney, the lysosomal changes were most prominent in the glomeruli and in the proximal tubules. The number of the lysosomes was very high. They contained homogenous, electron lucent material and additional electron dense, lipid-like droplets. In the brain biopsy specimens the number of abnormally large lysosomes was highest in the neurons but they were also present in the glial cells, pericytes and in the endothelial cells of capillaries. Their contents were more electron dense than those of the liver lysosomes. The differences in the lysosomal contents cannot at present be explained. Extrusion of the lysosomes into the kidney tubules is possible.
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  • 39
    ISSN: 1432-0533
    Keywords: Leucodystrophy Metachromatic ; Electron Microscopy ; Prismatic Deposits ; Brain ; Peripheral Nerve ; Kidney ; Rectum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Clinical history, light and electron microscopy findings are reported in four cases of infantile metachromatic leucodystrophy. By electron microscopy, the authors describe the various types of lesions and the different lipid deposits noticed in the central and peripheral nervous system, in the kidney and rectum. They stress the prismatic lipid deposits observed not only in the cerebral white matter and in the kidney but in the peripheral nerves as well.
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  • 40
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    Pflügers Archiv 331 (1972), S. 25-37 
    ISSN: 1432-2013
    Keywords: Growth Hormone ; Kidney ; Nephrectomy ; Liver ; Clearance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The metabolic clearance rate of125I-labelled sheep growth hormone (GH) in intact sheep was calculated to be 61±7.8 l/24 h and in nephrectomized sheep 26±3.9 l/24 h. From these figures a production rate of GH of 122 μg/24 h was derived for intact sheep. After a single intravenous injection of labelled GH the kidneys extracted more than 90% within 4 h. The extracted GH was metabolized by the kidney, only a small amount (5%) of the radioactivity excreted in the urine could be precipitated by perchloric acid. Renal metabolism of GH was also indicated by the appearance in renal venous blood of labelled material that was not immunoprecipitable. The liver also removed labelled GH and degraded it. Four hours after the injection of labelled GH most of the radioactivity was in blood and muscle, but there were significant amounts in kidney, liver and fat. Radioactivity that could be precipitated with GH-antiserum was found only in the kidney, thyroid and blood. A high percentage of activity extracted from all these tissues could still be precipitated by perchloric acid.
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  • 41
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    Pflügers Archiv 332 (1972), S. 28-39 
    ISSN: 1432-2013
    Keywords: Kidney ; Experimental Hypertension ; DOCA ; Specific Reabsorption Capacity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Rats were made chronically hypertensive by unilateral nephrectomy, repeated injections of desoxycorticosterone-acetate and offering saline as drinking fluid (DOCA-rats). Unilaterally nephrectomized animals (Nephrex-rats) were used for control. Compensatory renal hypertrophy was greater in DOCA-rats than in Nephrex-rats. Diameter and length of the proximal convolute in the DOCA-group increased more than in Nephrex-rats. GFR per unit kidney weight in the DOCA-group remained unchanged as compared to untreated Wistar-rats but increased significantly in Nephrex-animals. the water and sodium load of each nephron had doubled in both groups. Nevertheless, there were no substantial changes in the fractional water and sodium reabsorption in the different segments of the nephron of DOCA-rats as compared to normal animals. In Nephrex-rats fractional sodium and water reabsorption were increased in the proximal tubule and diminished in the loop of Henle and in the distal tubule. In Nephrex-rats an indirect correlation was found between blood pressure and both water reabsorption and the transit time of Lissamine green in superficial loops of Henle but no such correlation could be found in the DOCA-group. Determination of the specific reabsorption capacity of the proximal tubules during free-flow or using the split-drop technique yielded identical values in all animals studied.
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  • 42
    ISSN: 1432-2013
    Keywords: Kidney ; Goldblatt-Hypertension ; PAH-clearance ; PAH-Metabolism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary PAH-clearance studies were carried out separately on each kidney of both normal rats and rats with experimental Goldblatt-Hypertension. The rat and especially the rat kidney metabolizes a certain proportion of PAH-molecules 1. by splitting off the glycine-group forming p-aminobenzoate (PAB); 2. both PAH and PAB undergo partial N-acetylation. N-acetylated metabolites cannot be detected by the conventional analysis of PAH. Resorption of benzoates in the kidney results in a relatively high benzoate concentration in the renal vein. The complications created by these facts are discussed in relation to RPF-estimation using PAH. A correct determination of RPF by PAH is possible only if the analysis is carried out after an acid hydrolysis to make the detection of N-acetylated metabolites possible and if renal venous blood samples can be collected to correct for the reabsorbed benzoates. The clamped kidney of rats with Goldblatt-Hypertension is able to split glycine off from PAH but its capacity to N-acetylate is reduced. As a result identical PAH-clearances are found in both kidneys of these animals although their true RPF differ significantly.
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  • 43
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    Naunyn-Schmiedeberg's archives of pharmacology 275 (1972), S. 419-433 
    ISSN: 1432-1912
    Keywords: Rare Earths ; Gluconeogenesis ; Gluconeogenetic Key Enzymes ; Liver ; Kidney
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary After intravenous application of praseodymium nitrate, female Wistar rats develop a pronounced hypoglycemia which is due to an inhibition of hepatic gluconeogenesis. The renal gluconeogenesis remains uninfluenced. Among the gluconeogenetic key enzymes, pyruvate carboxylase and phosphoenolpyruvate carboxykinase are most drastically reduced in their activity, while there is only a slight effect on glucose-6-phosphatase and fructose-1,6-diphosphatase. An allosteric effect of praseodymium or a synthesis of an inhibitor caused by rare earths can be excluded. The activity of other enzymes which catalyse steps of both glycolysis and gluconeogenesis is not influenced. This selectivity of rare earths seems to indicate that there might be different genes for glycolysis and gluconeogenesis and led us to suppose that the site of action of rare earths is to be looked for at the nucleic acid system.
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  • 44
    ISSN: 1432-5233
    Keywords: Diabetes mellitus ; Glucose tolerance ; Kidney ; Leucine ; Serum growth hormone ; Serum insulin ; Tolbutamide ; Uremia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Dans le but de réduire au minimum les effets d'éventuelles erreus méthodologiques, l'évaluation des réponses des patients urémiques à l'administration orale de glucose et à celle intraveineuse de tolbutamide a été effectuée sur la base de l'augmentation ou de la diminution de la glycémie et de l'insulinémie. En effet les patients urémiques présentent une augmentation supérieure de la glycémie après administration orale de glucose. Dans les mêmes conditions l'augmentation de l'insulinémie est au contraire égale à celle des patients sains, tout en n'ayant aucune proportion avec l'augmentation des niveaux glycémiques. Cela démontre une oscillation ou un affaiblissement de la réponse insulinémique à l'hyperglycémie. Dans l'urémie, l'administration intraveineuse de tolbutamide provoque généralement une plus forte augmentation insulinémique et une plus forte diminution glycémique. Les patients urémiques tendent à avoir des niveaux sériques de l'hormone de la croissance plus élevés, soit avant que pendant le test oral de tolérance au glucose.
    Abstract: Resumen Para reducir todo lo posible los efectos de los eventuales errores metodológicos, se han valorado en términos de incrementos y disminuciones de la glicemia y de la insulinemia, las reacciones de pacientes urémicos al suministro oral de glucosa y de tolbutamida i.v. Tras suministro oral de glucosa, en los pacientes urémicos se observan incrementos mayores de la glicemia. Los incrementos de la insulinemia, en cambio, en esas misma condiciones, coinciden con los de los controles sanos, pero no guardan proporción con el aumento de los niveles glicémicos. Dicha pericia indica una oscilación o una debilitación de la reacción insulinémica a la hiperglicemia. En la uremia, el suministro i.v. de tolbutamida, generalmente provoca incrementos insulinémicos mayores y disminuciones glicémicas más intensas. Los pacientes urémicos tienden a presentar niveles serosos de hormón del crecimiento más altos, tanto antes como durante el test oral de tolerancia a la glucosa.
    Notes: Riassunto Per ridurre al minimo gli effetti di eventuali errori metodologici, le risposte dei pazienti uremici alla somministrazione orale di glucosio e a quella i.v. di tolbutamide sono state valutate in termini di incrementi e decrementi della glicemia e dell'insulinemia. Dopo somministrazione orale di glucosio si osservano, nei pazienti uremici, maggiori incrementi della glicemia. Gli incrementi dell'insulinemia sono invece, in queste stesse condizioni, uguali a quelli dei controlli sani, ma non proporzionati all'aumento dei livelli glicemici. Tale reperto è indicativo di una oscillazione o di un indebolimento della risposta insulinemica all'iperglicemia. Nell'uremia, la somministrazione i.v. di tolbutamide provoca generalmente maggiori incrementi insulinemici e maggiori decrementi glicemici. I pazienti uremici tendono ad avere più elevati livelli sierici di ormone della crescita, sia prima che nel corso del test orale di tolleranza al glucosio.
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  • 45
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    Acta diabetologica 9 (1972), S. 655-687 
    ISSN: 1432-5233
    Keywords: Chinese hamster ; Diabetes ; Glycogen infiltration ; Kidney ; Nuclear glycogenosis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Cette enquête sur l'ultra-structure du rein de hamsters chinois atteints de diabète a permis de relever des lésions glomérulaires légères, consistant en un épaississement non-homogène des membranes basales des vaisseux capillaires, des altérations de cellules de la mésange, une dilatation irrégulière des anses vasculaires. Sur la partie tubulaire, une accumulation de glycogène dans le cytoplasme des cellules de la partie distale et du tube collecteur ainsi que la présence de glycogène dans le noyau des animaux atteints d'un grave diabète et de kétose.
    Abstract: Resumen La presente investigación sobre la ultraestructura del riñón del hamster chino diabético, ha dado la posibilidad de poner en evidencia sutiles lesiones glomerulares, consistentes en el engrosamiento no homogéneo de las membranas basales de los vasos capilares, en alteraciones de las células del mesangio, en la dilatación irregular de las ansas; y, a cargo de la parte tubular, en una acumulación de glicógeno en el citoplasma de las células del tramo distal y del túbulo colector y en la presencia de glicógeno en el núcleo de los animales con diabetes grave y quetosis.
    Notes: Riassunto La presente indagine sulla ultrastruttura del rene di hamsters cinesi diabetici ha fatto rilevare fini lesioni glomerulari, consistenti in ispessimento non omogeneo delle membrane basali dei vasi capillari, alterazioni delle cellule del mesangio, dilatazione irregolare delle anse vascolari. A carico della parte tubulare, accumulo di glicogeno nel citoplasma delle cellule del tratto distale e del tubulo collettore; presenza di glicogeno nel nucleo negli animali con diabete grave e chetosi.
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  • 46
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    Cell & tissue research 134 (1972), S. 193-204 
    ISSN: 1432-0878
    Keywords: Kidney ; Anurans ; Canaliculi cells ; Dark cells ; Electron microscopy, Enzyme cytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die elektronenmikroskopische und enzymcytochemische Untersuchung der Nieren von Rana cancrivora und R. esculenta, Hyla arborea und H. regilla, Bufo carens, B. mauretanicus und B. viridis ergibt, daß im Epithel ihrer Verbindungsstücke verschiedene Zelltypen vorkommen. Die Verbindungsstücke von Rana cancrivora und R. esculenta zeichnen sich — abgesehen von dem Vorhandensein heller Zellen — durch den Besitz sog. Kanälchenzellen aus, die nach Form und Struktur an die Belegzellen der Magendrüsen erinnern. Es handelt sich um sehr mitochondrienreiche, elektronendicht erscheinende Elemente, die durch teilweise verzweigte intrazelluläre Kanälchen mit der Lichtung des Verbindungsstückes kommunizieren. Aus der Oberfläche dieser Canaliculi ragen kurze Cytoplasmafortsätze in das Lumen. An der Basis der Kanälchenzellen bilden zahlreiche Cytoplasmafortsätze ein Labyrinth, das mit den seitlichen Interzellularräumen in Verbindung steht. Die Kanälchenzellen geben eine starke Reaktion auf Bernsteinsäuredehydrogenase und NADH-Diaphorase, die dem Reichtum der Zellen an Mitochondrien entspricht. Unterschiede in der Zahl der Kanälchenzellen bei dem marinen Frosch Rana cancrivora und bei R. esculenta scheinen nicht zu bestehen. Im Verbindungsstück der untersuchten Hyla- und Bufoarten fallen dunkle, d.h. elektronendichte Zellen auf, die zwar viele Mitochondrien enthalten und ein basales Labyrinth bilden, jedoch nicht kanalisiert sind. Auch diese dunklen Zellen geben eine intensive Reaktion auf Bernstein- säuredehydrogenase und NADH-Diaphorase. Die Kanälchenzellen weisen Zeichen einer sekretorischen Aktivität (Bildung von Mukosubstanzen) auf. Die Frage, ob sie außerdem resorptiv tätig sind und ob die dunklen Zellen sowohl sezernieren als auch Ionen aktiv transportieren, kann mit den angewandten Methoden nicht beantwortet werden. Unbekannt ist ferner, ob die Unterschiede im Aufbau der Verbindungsstücke bei den Rana-Arten auf der einen und den Hyla- und sowie Bufo-Arten auf der anderen Seite zu Verschiedenheiten der Harnbildung bei diesen Formen in Beziehung stehen.
    Notes: Summary The electronmicroscopical and enzymecytochemical investigation of the kidneys of Rana cancrivora, R. esculenta, Hyla arborea, H. regilla, Bufo carens, B. mauretanicus and B. viridis reveals that the epithelium of the connecting tubule (Verbindungsstück) consists of different cell typs. The connecting tubules of Rana cancrivora and R. esculenta are characterized — apart from the occurrence of light cells — by the differentiation of so-called canaliculi cells, the shape and structure of which resemble those of the parietal cells of the gastric glands. These electron dense elements are rich in mitochondria and communicate by partly ramified intracellular canaliculi with the lumen of the connecting tubule. The plasma membrane bordering the canaliculi forms short microvilli-like processes. At the basis of the canaliculated cells numerous cytoplasmic processes form a labyrinth which is in connection with the lateral intercellular space. The canaliculi cells exhibit a strong activity of succinic dehydrogenase and NADH-diaphorase, which corresponds to the abundance of mitochondria in these cells. Differences in the number of canaliculi cells in the marine frog Rana cancrivora and the freshwater species Rana esculenta apparently do not exist. The connecting tubules of the Hyla and Bufo species investigated contain strikingly dark, i.e. electron dense cells, which contain numerous mitochondria, and which possess a basal labyrinth. Canaliculi, however, are lacking. These dark cells, too, give an intensive reaction for succinic dehydrogenase and NADH-diaphorase. The canaliculi cells show features of a secretory activity (production of mucous substances). The question, whether in addition they have a resorptive function and whether the dark cells are secretory and actively ion-transporting elements, cannot be answered by means of the methods applied. Further, it remains unknown whether the differences in the structure of the connecting tubule of the Rana species on the one hand and the Hyla-and Bufo species on the other, are related to differences in the mechanisms of urine production.
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  • 47
    ISSN: 1432-0878
    Keywords: Kidney ; Rat ; Actin- and myosin-like filaments ; Tubule and interstitial cells ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary By electron microscopy, the prominent bundles of filaments occurring in the basal part of proximal and distal tubule cells and in interstitial cells of rat kidney cortex were studied in cells fixed by vascular perfusion, in glycerol-extracted cells and in glycerol-extracted cells treated with heavy meromyosin (HMM). The studies of perfusion-fixed tissue showed that the proximal tubule cells contained in their most basal part filamentous bundles oriented transversely around the tubule. The bundles consisted of trightly packed thin filaments (50–80 Å in diameter). Similar but less prominent bundles were found in distal tubule cells and in interstitial cells. The dimension of these filaments was similar to that of actin filaments and their insertion in the basal cell membrane of the tubule epithelial cells resembled the insertion of actin filaments in the cell membrane of smooth muscle cells. The studies on glycerol-extracted cells revealed that some tubule cells contained two types of filaments (60–80 Å and 130–170 Å in diameter) located side by side in the basal filamentous bundles. The dimension of the thick filaments corresponds well to the values for myosin filaments in glycerinated smooth and skeletal muscle. The studies on HMM-reacted renal tissue revealed that the thin filaments (60–80 Å) described in tubule and interstitial cells are probably actin filaments, as they formed characteristic arrowhead complexes morphologically indistinguishable from the complexes of HMM with actin filaments in smooth and striated muscle cells. Our results provide strong evidence that a two-filament contractile system, based on interaction of actin and myosin filaments, exists in renal tubule and interstitial cells. As a hypothesis it is proposed that it is changes in tonus of the basal filamentous system in the proximal tubule cells which stabilize the intratubular pressure, possibly via angiotensin.
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  • 48
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    Cell & tissue research 123 (1972), S. 96-111 
    ISSN: 1432-0878
    Keywords: Kidney ; Stickleback ; Mucous cells ; Sexual hormones
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Au microscope électronique, l'action de la méthyltestostérone sur les cellules rénales de l'Epinoche femelle se traduit par une cytodifférenciation conduisant à la formation de cellules glandulaires muqueuses. Elle a lieu simultanément à deux niveaux distincts: Au niveau du tubule proximal, le premier signe visible de cytodifférenciation est une activation du nucléole, accompagnée par une augmentation de taille des cellules. Puis on assiste à un développement de l'ergastoplasme et de l'appareil de Golgi et à l'élaboration de deux types de sécrétions: d'abord des granules de 2000–2500 Å, ensuite des grains de mucigène typiques, qui subissent rapidement une transformation muqueuse. Une cytodifférenciation régressive intervient en même temps. Elle concerne la pinocytose apicale qui disparaît. Au niveau des tubules collecteurs, la cytodifférenciation se traduit par la formation d'un mucus hyalin d'origine golgienne. Elle s'accompagne également d'une disparition de la pinocytose. La méthyltestostérone est capable de provoquer, chez la femelle, une cytodifférenciation rénale identique à celle que l'on observe chez le mâle pendant la période de reproduction. La transformation muqueuse des cellules rénales est donc sous le contrôle de la seule testostérone, qui déclenche au niveau cellulaire un ensemble de processus conduisant à la formation de mucus. Au microscope électronique, on constate que l'élaboration de mucus prêt à l'excrétion est achevée au bout de trois jours dans les tubules proximaux alors que dans les tubules collecteurs elle ne demande que 24 heures.
    Notes: Summary At the microscopic level, the action of methyl testosterone on the cells of the kidney of the female three-spined Stickleback gives raise to a cytodifferentiation which leads to the formation of mucous glandular cells. This action is evident at two different levels: At the level of the proximal tubule, the first visible sign of cytodifferentiation is an activation of the nucleolus, accompanied by a growth of the cell size. Then a rapid development of the ergastoplasm and the Golgi apparatus takes place, which leads to the elaboration of two types of secretory particles: granules of 2000–2500 Å in diameter appear first, then typical mucigen granules become visible. These latter undergo a rapid mucous transformation. A regressive cytodifferentiation occurs at the same time. It concerns the apical pinocytosis which disappears in the cells undergoing the glandular differentiation. At the level of the collecting tubules, the cytodifferentiation is characterized by the elaboration of a clear mucus which originates in the Golgi apparatus and migrates to the apex of the cells. A disappearance of the pinocytosis is also noticeable. In the kidney of the female, methyl testosterone induces a cytodifferentiation which is identical to that occuring in the male during the breeding period. So the mucous transformation of renal cells is under the control of a single hormone: the testosterone, which is able to give raise to a succession of phenomena leading to the formation of a mucous secretion. With the electron microscope, it is possible to demonstrate that three days are necessary for the elaboration of the mucus ready to be discharged in the lumen of the renal proximal tubules. In the collecting tubules, the reaction occurs more quickly, after only two days of treatment.
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  • 49
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    Pflügers Archiv 330 (1971), S. 136-148 
    ISSN: 1432-2013
    Keywords: Kidney ; Na+−K+-ATPase ; Sodium Transport ; Volume Expansion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The role of renal Na+−K+-ATPase in the acute changes in sodium reabsorption caused by isotonic volume expansion was evaluatedin vivo andin vitro in the rat and the dog. Duringin vivo volume expansion with isotonic saline in the rat, renal medullary Na+−K+-ATPase specific activity increased, while the simultaneously determined cortical Na+−K+-ATPase specific activity and kinetics remained unchanged. Furthermore, experimentsin vitro failed to demonstrate a circulating inhibitor of renal Na+−K+-ATPase both in plasma dialysates from volume-expanded rats and in plasma dialysates concentrated 20-fold by ultrafiltration from volume-expanded dogs. These results suggest that the decreased proximal tubular reabsorption of sodium during volume expansion is not mediated by inhibition of renal cortical Na+−K+-ATPase. The acute increment in medullary Na+−K+-ATPase observed could represent an adaptive response to increased sodium reabsorption by the loops of Henle, and raises the possibility that this enzyme may participate in relatively rapid adjustments in the transport of sodium by the renal tubule.
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  • 50
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    Pflügers Archiv 324 (1971), S. 1-25 
    ISSN: 1432-2013
    Keywords: Adenosine Triphosphatase ; Plasma Membrane Enriched Fraction ; Microsomes ; Kidney ; ATPase ; zellmembranangereicherte Fraktion ; Mikrosomen ; Niere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A fraction enriched with plasma cell membranes (PMF) was isolated from rat kidney homogenate by differential centrifugation. Before NaJ treatment electron micrographs of the preparation showed a membraneous fraction with only a small contamination of mitochondria. After treatment with NaJ the residual PMF exhibited a low microsomal glucose 6-phosphatase activity. Marker enzymes of other subcellular fractions were not detected. The NaJ extracted PMF revealed a high specific activity of ATPase, 91% of which was stimulated by Na+ and K+. The MgNaK-ATPase was characterized by Michaelis Menten kinetics. In contrast, Hill coefficients (“n”) of NaK-ATPase for the activation by Na+, K+ and Mg-ATP were greater than one. Experiments with various nucleotide tri-, di- and monophosphates revealed a high substrate specificity of the NaK-ATPase. The pH optimum was in the range of 7.2. SH-reagents and ouabain depressed the Na+ and K+ stimulated enzyme activity. PMF isolated from rat kidneys exhibited an acylphosphatase and a nitrophenylphosphatase activity, both of which were stimulated by K+. Furthermore 5′-nucleotidase and leucine aminopeptidase activities were present in the fraction.—Thus, NaK-ATPase of the PMF revealed the typical properties of the NaK-ATPase demonstrated in the microsomal preparations, which has been referred to by Skou (1965) as the enzymatic basis of active cation transport.
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  • 51
    ISSN: 1432-2013
    Keywords: Na-K ATPase ; Liver ; Kidney ; Diurnal Variation ; Na-K ATPase ; Leber ; Niere ; Tagesrhythmus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In a systematic investigation the course of the activities of the Na-K activated ATPase and the Mg ATPase enzyme systems in rat liver and kidney were studied. In the liver the activities of both enzyme systems were on a significantly higher level (22 and 15% resp.) during the evening hours (4:00 p. m. to 2:00 a. m.). In the kidney a significantly lower level (13%) of Na-K ATPase activity was found during the night (10:00 p. m. to 8:00 a. m.), while Mg ATPase activity did not vary significantly. The periods of raised enzyme activity in liver and in kidney did not coincide. The results are discussed in relation to literature data on diurnal variations of metabolic activities in general.
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  • 52
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    Pflügers Archiv 327 (1971), S. 152-166 
    ISSN: 1432-2013
    Keywords: Kidney ; Renal Artery ; Blood Flow Velocity ; Isoproterenol ; β-adrenergic Receptors ; Niere ; Nierenarterie ; Nierendurchblutung ; Isoproterenol ; β-Receptoren
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An wachen Hunden wurden mit einem Miniaturdruckaufnehmer der Blutdruck in der abdominalen Aorta und mit einem elektromagnetischen Flußmesser die Strömungsgeschwindigkeit in der linken Nierenarterie gemessen. Die Reaktion der Nierenstromstärke und des Blutdrucks auf rasche (〈1 sec) Injektion von 2,5, 5,0, 10,0 und 20,0 μg Isoproterenol in die abdominale Aorta proximal der Nierenarterie wurde untersucht. Bei allen vier Dosen wurde regelmäßig eine Steigerung der Nierendurchblutung und eine Abnahme des arteriellen Blutdrucks beobachtet. Die maximale Widerstandssenkung betrug im Mittel 25–30%. Während der ersten 6 sec nach Injektion erreichte die Nierenstromstärke bei noch unverändertem arteriellen Mitteldruck einen signifikant erhöhten Wert. Ebenso fand sich eine signifikant erhöhte Stromstärke, nachdem der Blutdruck sein Ausgangsniveau wieder erreicht hatte. Nach β-Blockade mit 0,5 mg/kg Propranolol hatte Isoproterenol in den verwendeten Dosen keinen Einfluß auf die Nierenstromstärke und den arteriellen Blutdruck. Das Ausmaß der beobachteten Vasodilatation läßt sich durch Autoregulation nicht erklären. Aus den Experimenten wird geschlossen, daß Isoproterenol (2,5 bis 20,0 μg i.a.) am wachen Hund in Ruhe β-Receptoren der Nierengefäße erregt.
    Notes: Summary In unanesthetized dogs abdominal aortic pressure was measured with an implanted miniature transducer, left renal artery flow velocity by an electromagnetic flowmeter. The effect of rapid injections (〈1 sec) of 2.5, 5.0, 10.0 and 20.0 μg isoproterenol into the abdominal aorta proximal to the renal artery on kidney blood flow and arterial blood pressure was investigated. Isoproterenol in every dose used regularly caused kidney blood flow to increase and arterial blood pressure to fall. The maximum decrease of resistance to flow in the average amounted to 25–30%. During the first 6 sec after drug injection kidney blood flow was already significantly elevated while arterial blood pressure was still unchanged.A significantly augmented kidney blood flow was also found when blood pressure had returned again to its original level. After β-blockade (0,5 mg/kg propranolol) isoproterenol (2.5–20.0 μg i.a.) had no effect on kidney blood flow and arterial blood pressure. The extent of the vasodilation cannot be attributed to autoregulation. It is concluded, that isoproterenol (2.5–20.0 μg i.a.) causes a β-adrenergic vasodilation in the kidney vasculature of the resting conscious dog.
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  • 53
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    Naunyn-Schmiedeberg's archives of pharmacology 271 (1971), S. 93-102 
    ISSN: 1432-1912
    Keywords: Carbohydrate Metabolism ; Kidney ; Enzymic Determination of Substrates ; 6-Aminonicotinamide ; Adrenalectomy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary After application of 6-aminonicotinamide (6-AN), a strong accumulation of 6-phosphogluconate was found in rat kidney. The accumulation of 6-phosphogluconate influences the activity of the phosphoglucose isomerase. The enzymic determination of the substrate concentrations of the carbohydrate metabolism after application of 6-AN revealed that fructose-6-phosphate and lactate as well as phosphoenolpyruvate are significantly increased in the kidney as compared to the controls. The increase in phosphoenolpyruvate might be caused by stimulated gluconeogenesis, as the application of 6-AN increases the release of corticosterone from the adrenal cortex. After adrenalectomy, the accumulation of 6-phosphogluconate is decreased, the ratio glucose-6-phosphate/fructose-6-phosphate is normalized, and also the values for lactate and phosphoenolpyruvate decrease. The effects of adrenaline seem to involve the passage of glucose through the pentose phosphate pathway. There is probably a relationship between the blockade of the oxidative pentose phosphate pathway and the stimulation of gluconeogenesis in the kidney, the mechanism of which is unknown. In contrast to the findings in the brain, no changes could be established in the concentrations of citrate and 2-oxoglutarate.
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  • 54
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    Cell & tissue research 114 (1971), S. 203-219 
    ISSN: 1432-0878
    Keywords: Kidney ; Triturus cristatus ; Juxtaglomerular apparatus ; Cell types
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary 1)As in mammals, the juxtaglomerular apparatus of the Newt (Triturus cristatus) is composed by cells of the media of the afferent glomerular arteriole and by cells of the intermediary tubule. 2) The cells of the media of the glomerular arteriole are of two different types: granular and agranular cells. 3) The intermediary tubule is formed by dark and light cells. 4) Part of interrenal body is located close to glomerular arteriole and intermediary tubule.
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  • 55
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    Cell & tissue research 114 (1971), S. 1-21 
    ISSN: 1432-0878
    Keywords: Kidney ; Elasmobranchs ; Glomerular Vessels ; Tubular Secretion ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Glomerula und Hauptstücke der Elasmobranchierniere fallen nach lichtmikroskopischen Studien durch strukturelle Besonderheiten auf, die möglicherweise mit der physiologischen Uraemie dieser Tiergruppe in Zusammenhang stehen. Um weitere morphologische Grundlagen für spätere cytochemische und physiologische Untersuchungen zu gewinnen, haben die Autoren die genannten Nephronabschnitte elektronenmikroskopisch untersucht. Folgende Befunde wurden erhoben: 1. Die erstaunliche Dicke der Glomerulumgefäße der Elasmobranchier — sie beträgt durchschnittlich 7 μ — beruht auf der Ausbildung einer zellreichen Schicht (Durchmesser durchschnittlich 6 μ) zwischen Podozyten und Endothel. 2. Die Podozyten tragen Einzelcilien, die in den Kapselraum hineinragen, und werden von Strähnen zarter, etwa 80 Å dicker Filamente durchzogen. Möglicherweise handelt es sich um Myofilamente. Zwischen den Füßchen der Podozyten auf der Basalmembran kommen Schlitzmembranen vor. 3. Die Mittelschicht der Gefäßwand entspricht einer stark verdickten Basalmembran, in die außer Kollagenfibrillen Zellen eingebettet sind. Die Mehrzahl dieser intralamellären Zellen besteht aus verästelten Elementen, deren Ausläufer sich innerhalb der Membran ausbreiten. Im Gegensatz zu früheren Aussagen, die sich auf lichtmikroskopische Beobachtungen stützen, werden diese Zellen als fibrozytäre Elemente und nicht als glatte Muskelzellen gedeutet. Eine zweite intralamelläre Zellart, deren Elemente keine Ausläufer besitzen, fällt durch starke Entwicklung von Ergastoplasma auf. 4. Das relativ dicke Endothel der Glomerulumgefäße besitzt eine stark zerklüftete Oberfläche, seine Pseudofenestrierung ist weniger regelmäßig als in den Glomerula höheren Formen ausgebildet. 5. Verschiedene Zustandsbilder einer Abschnürung von vacuolär strukturierten Blasen und von Protuberanzen, die möglicherweise das Äquivalent einer apokrinen Extrusion aus den Hauptstückzellen sind, werden beschrieben. Die Frage bleibt offen, ob dieser Vorgang etwas mit der Abgabe harnpflichtiger Substanzen in das Lumen des Kanälchens zu tun hat. Es handelt sich bei diesen Strukturen nicht um Fixationsartefakte. 6. Die von Lichtmikroskopikern beschriebenen „Basalreifen“ des Nierenkanälchens entsprechen leistenartigen Erhebungen der Innenfläche der Basalmembran. Das Bild der „basalen Kittfäden“ dürfte durch die Cytoplasmapartien zwischen den Basalreifen hervorgerufen werden.
    Notes: Summary According to light microscopical studies glomerula and proximal convoluted tubules of the elasmobranch kidney are characterized by structural peculiarities, which possibly are related to the physiological uremia of this group of animals. In order to obtain morphological fundamentals for cytochemical and physiological studies, the authors have investigated the above mentioned parts of the nephron with the electron microscope. The results are as follows: 1. The remarkable thickness of the glomerular tufts in the elasmobranchs—averaging 7 μ—is due to the presence of a cell-rich layer (diameter about 6 μ) between podocytes and endothelium. 2. The podocytes bear individual cilia protruding into the capsular space. They further contain bundles of fine filaments (diameter approximately 80 Å) which possibly are myofilaments. Between the feet of the podocytes slit membranes occur on the surface of the basement lamina. 3. The medium layer of the vascular wall corresponds to a strongly thickened basement lamina, into which besides collagen fibrils and fuzzy material different cells are embedded. The majority of these intralamellar cells consists of branched elements the processes of which spread inside the membrane. In contrast to earlier statements, which were based on light microscopical observations, these cells are interpreted to represent fibrocytic elements and not smooth muscle cells. A second intralamellar cell type which does not possess any processes, is marked by well developed cisternae of rough endoplasmic reticulum. 4. The relatively thick endothelium of the glomerular vessels possesses a rugged surface, its pseudofenestration beeing less regular than in glomerular capillaries of higher vertebrates. 5. Vesiculated spherical bodies, swollen cellular apices and protuberances apparently being pinched off in the proximal convoluted tubule—possibly equivalents of an apocrine extrusion—are described. The authors are of the opinion that these structures do not represent artifacts caused by fixation. It remains on open question, whether this extrusion contributes to the composition of the tubular urine. 6. The “Basalreifen” of the kidney tubule as have been described by light microscopists, correspond to crests of the inner surface of the basement lamina, the “basale Kittfäden” to the strips of cytoplasm between these “Basalreifen”.
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  • 56
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    Cell & tissue research 120 (1971), S. 29-36 
    ISSN: 1432-0878
    Keywords: Kidney ; Macula densa ; Juxtaglomerular apparatus ; Bird ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The macula densa (MD) site of the kidney, at which the distal tubule is attached to the vascular pole of the glomerulus, was examined with the light microscope in domestic fowl and Japanese quail; and in the fowl also with the electron microscope. The characteristics of mammalian MD cells, as reported in the literature, are compared with those of the cells in the avian MD site. The avian cells possess some of the characteristics of mammalian MD cells and they are distinguishable from the cells in adjacent portions of the distal tubule. The Golgi system in the avian cells is apical to the nucleus, unlike in mammals where its location is basal. The cells in the avian MD sites can be considered as structurally transitional between the typical MD cells in mammals and the ordinary cells of the distal tubule. These findings are discussed in relation to the function of the avian kidney and to its control by the renin mechanism.
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  • 57
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    Cell & tissue research 118 (1971), S. 326-332 
    ISSN: 1432-0878
    Keywords: Kidney ; Mesangium ; Hibernator ; Juxtaglomerular apparatus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The mesangial and juxtaglomerular cells were studied in kidneys of hibernating and non-hibernating ground squirrels, Citellus tridecemlineatus. In the hibernating animal, as compared with the non-hibernating, the mesangial cells show signs of increased activity. The cells are relatively larger, and numerous vacuoles appear in the cytoplasm. The juxtaglomerular cells also show signs of hyperactivity. Secretion droplets, mitochondria and free ribosomes increase in number and the endoplasmic reticulum becomes dilated. It is postulated that during hibernation, increased activity of mesangial cells slows glomerular filtration by absorption of filtrate into the mesangial matrix, and increased activity of juxtaglomerular cells results in increased renin secretion which in turn may stimulate hypersecretion of aldosterone to conserve sodium for water balance mechanisms necessary at the time.
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  • 58
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    Clinical and experimental medicine 156 (1971), S. 216-231 
    ISSN: 1591-9528
    Keywords: Kidney ; Glomerulus ; Isolation technique ; Ultrastructure ; Niere ; Glomerulum ; Isoliertechnik ; Ultrastruktur
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Mit einer im Detail angegebenen, mechanisch schonenden Sieb-Methode wurden aus Rattennieren Glomerulumfraktionen mit einem Reinheitsgrad von 95–98% gewonnen. Dabei wurden 10 verschiedene Spülmedien benützt und ihr Einfluß auf die Ultramorphologie der Glomerula elektronenmikroskopisch kontrolliert. Nach Verwendung einer Krebs-Henseleit-Bicarbonat-Lösung mit einem pH von 7,9 ist mit der irreversiblen Schädigung des überwiegenden Teiles der Podocyten zu rechnen. Elektronenmikroskopisch befriedigende Resultate ließen sich mit einer Krebs-Henseleit-Bicarbonat-Lösung pH 7,4+3% Dextran erzielen, bei der ca. 60% der in der Fraktion enthaltenen Podocyten intakt blieben. Die restlichen 40% Podocyten waren in erster Linie mechanisch zerstört. Während Endothel- und Mesangiumzellen nach den verschiedenen Spülmedien kaum morphologische Veränderungen aufweisen, können also die Podocyten je nach Spülmedium überwiegend zerstört werden oder zu etwa 60% erhalten bleiben.
    Notes: Summary Fractions with 95–98% glomeruli have been obtained from rat kidneys with a sieve method described in detail. 10 different rinsing solutions have been used during isolation and their influence on the ultrastructure of the glomeruli has been controlled electron microscopically. The podocytes exhibit a strong edema of cytoplasm and nucleus, reaching up to cytolysis, after Krebs-Henseleit-bicarbonate-, Krebs-Ringer-phosphate- and Robinson-solution. After a Krebs-Henseleit-bicarbonate solution with pH 7.9 instead of pH 7.4 most podocytes have been damaged irreversibly. A satisfying ultrastructure resulted after solutions with a higher colloid osmotic pressure or osmotic pressure. The best results have been obtained with Krebs-Henseleit-bicarbonate solution pH 7.4+3% dextran (mol wt 40000), after which about 60% of the podocytes have been calculated to be intact. 40% of the podocytes in this fraction mainly were mechanically damaged. While endothelium and mesangium show only minor structural aberrations after the different rinsings, thus most podocytes are damaged irreversibly after Krebs-Henseleit-bicarbonate pH 7.9, and on the other hand about 60% may be intact after Krebs-Henseleit-bicarbonate pH 7.4+3% dextran.
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  • 59
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    Anatomy and embryology 131 (1970), S. 111-147 
    ISSN: 1432-0568
    Keywords: Kidney ; Lymphatic vessels ; Lymphatic capillaries ; Lymphatic valves ; Mammals
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Lymphgefäße der Niere folgender Tiere wurden untersucht: Hund, Katze, Meerschweinchen, weiße Ratte, Bisamratte, Wüstenmaus (Meriones), weiße Maus und Goldhamster. Bei allen Tieren fanden wir einen prinzipiell gleichartigen Aufbau des Nierenlymphgefäßsystems. Die Lymphgefäße der Niere beginnen als Lymphcapillaren im Bereich der Arteriae interlobulares; diese Interlobular-Lymphgefäße münden an der Rindenmarkgrenze in die schon klappenführenden Arcuata-Lymphgefäße, die ihrerseits mit den Vasa arcuata verlaufen. Daraus gehen die klappenreichen Interlobar-Lymphgefäße hervor, die schließlich als wenige Hilus-Lymphgefäße die Niere verlassen. Abseits der großen Blutgefäße im eigentlichen Parenchym der Nierenrinde sowie des Nierenmarkes gibt es keine Lymphgefäße oder Lymphcapillaren. Neben diesen intrarenalen Lymphgefäßen finden sich subcapsuläre Lymphgefäße bei Tieren, die ein ausgeprägtes Venennetz an der Nierenoberfläche besitzen (Katze). Diese subcapsulären Lymphgefäße verlaufen mit den Venen oberflächlich zum Nierenhilus. In diese subcapsulären Lymphgefäße münden Lymphgefäße aus der Nierenkapsel ein; die Kapsel-Lymphgefäße selbst wurden nicht untersucht. Verbindungen zwischen den Lymphgefäßen an der Nierenoberfläche und den intrarenalen Lymphgefäßen sind nur gegeben durch Lymphgefäße, die mit Arteriae capsulares (= starke, zur Kapsel durchlaufende Interlobular-Arterien) verlaufen. Solche Arterien kommen jedoch nur bei einem Teil der von uns untersuchten Tiere in geringer Anzahl vor (Hund, Wüstenmaus). Die Interlobular-Lymphgefäße sind Lymphcapillaren, deren Wand von einem,dünnen, aber geschlossenen Endothel ohne Basalmembran gebildet wird. Die Arcuata-sowie Interlobar-Lymphgefäße (ebenso die subcapsulären Lymphgefäße) sind größtenteils dem Typus der “postcapillären Lymphgefäße” zuzurechnen; diese Lymphgefäße führen schon Klappen, haben jedoch einen weitgehend capillären Wandbau. Alle Lymphgefäße der Niere liegen eingebettet in einem sehr lockeren kollagenen Bindegewebe, welches die großen Blutgefäße der Niere, vorwiegend die Arterien umgibt. Es wird vermutet, daß die Zusammenarbeit dieses paravasalen Bindegewebes und der Lymphgefäße einen Lymphabfluß aus dem Parenchym der Nierenrinde ermöglicht; für das Nierenmark dagegen ist kein Lymphabfluß vorstellbar.
    Notes: Summary The lymphatic vessels of the kidney have been investigated in the following animals: dog, cat, guinea pig, white rat, muskrat (Ondatra zibethica), white mouse, syric hamster and a desert rodent (Meriones shawii). It has been found that in all these animals there is a similar organisation of the lymphatic system of the kidney. The lymphatic vessels of the kidney originate as lymphatic capillaries in the area of interlobular arteries; at the corticomedullary junction the interlobular lymphatic capillaries drain into the arcuate lymphatic vessels which are already provided with valves. The arcuate lymphatic vessels continue as interlobar lymphatic vessels and become confluent towards the hilus to form few hilar lymphatic vessels leaving the kidney; the interlobar and hilar lymphatic vessels have very numerous valves. Lymphatic vessels have only been found accompanying the large blood vessels and none have been found among the tubules of the renal cortex and medulla. There also exist subcapsular lymphatic vessels in animals which have a well developed venous system on the renal surface (cat). The subcapsular lymphatic vessels accompany the superficial veins to the renal hilus. Lymphatic vessels from the renal capsule drain into subcapsular lymphatic vessels; the capsular lymphatic system itself has not been investigated. Lymphatic vessels which accompany capsular arteries are the only connections between the intrarenal lymphatic vessels and the lymphatic vessels on the surface of the kidney. Such capsular arteries (= interlobular arteries which reach the renal capsule), however, only exist in few of the investigated animals (dog, Meriones) in a very small number. The wall of the interlobular lymphatic capillaries is formed by a single layer of thin endothelial cells without a basement membrane. The arcuate and the interlobar lymphatic vessels (the subcapsular lymphatics, too) mostly represent a postcapillary type: these lymphatic vessels are provided with valves; their wall, however, often consists of an endothelium only. All lymphatic vessels of the kidney lie in a loose connective tissue which surrounds the large blood vessels of the kidney — especially the arteries. It is supposed that a lymphatic drainage of the renal cortex is possible by the co-operation of this paravasal connective tissue and the lymphatic vessels; a lymphatic drainage of the renal medulla appears to be impossible.
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  • 60
    ISSN: 1432-2013
    Keywords: Kidney ; Concentration ; Corticomedullary Gradients ; Urea ; Electrolytes ; Niere ; Konzentration ; Corticomedulläre Gradienten ; Harnstoff ; Elektrolyte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Um Aussagen über die Konzentrierungsmechanismen im äußeren und inneren Mark der Säugetierniere machen zu können, wurden die Konzentrationsprofile von Natrium, Kalium und Harnstoff im Nierengewebe bei verschiedenen Funktionszuständen ermittelt. Zu diesem Zweck wurden Ratten über einen Magenverweilkatheter Lösungen mit ansteigenden Konzentrationen von NaCl oder Harnstoff oder Kombinationen von diesen beiden Stoffen zugeführt. Nach Erreichen des Konzentrationsmaximums im Urin wurden die Tiere getötet und sodann der Harn sowie das Gewebe der Nierenrinde, des äußeren und des inneren Markes auf ihren Gehalt an Natrium, Kalium und Harnstoff analysiert. Es wird gefunden: 1. Bei alleinigem NaCl-Angebot steigen, die Natriumkonzentrationen im äußeren Mark stark und im inneren Mark nur noch wenig an. Die Natriumkonzentrationen ändern sich wenig mit steigendem Harnfluß. Die Harnstoffkonzentrationen steigen im inneren Mark nicht an und liegen in der Papillenspitze über den Harnkonzentrationen. 2. Bei alleinigem Harnstoffangebot steigen die Harnstoff- und Natriumkonzentrationen bei kleinem Harnfluß kontinuierlich bis zur Papille an. Bei starkem Harnfluß steigen die Harnstoffkonzentrationen im inneren Mark wesentlich geringer an, und fallen die Natriumkonzentrationen nach einem Anstieg im äußeren Mark zum inneren Mark hin wieder ab. 3. Werden NaCl und Harnstoff gleichzeitig in hoher Konzentration angeboten, sossteigen sowohl die Harnstoff- als auch die Natriumkonzentrationen bis zur Papillenspitze hin an. ParaDie Befunde sprechen dafür, daß im äußeren und inneren Mark unterschiedliche Konzentrierungsmechanismen wirksam sind. Ein hypothetisches Modell für die Konzentrierungsprozesse im inneren Mark wird diskutiert.
    Notes: Summary To investigate the mechanisms of concentration in the outer and inner medulla of the kidney solutions with rising concentrations of urea or NaCl were infused into the stomach of anaenesthesized rats. When the concentration maxima in the urine were reached, the rats were killed and the tissue of the kidneys was analysed for urea, sodium and potassium. The following results, were obtained: 1. Offering NaCl only the sodium concentration increased mainly in the outer medulla and the concentration profile was nearly independent from the urine flow. The urea concentration was constant throughout the inner medulla and in the papilla higher than in the urine. 2. Offering urea only and for slow rates of urine flow, the sodium and urea concentration rose continously towards the papilla while with increasing distance from the cortex the sodium concentration first increased (within the outer, medulla) then decreased again. 3. Offering NaCl and urea together the sodium and urea concentration increased in the outer as well as in the inner medulla. These results support the hypothesis that the mechanism of concentration of sodium and urea in the outer medulla differs considerably from that in the inner medulla; a model for the latter mechanism is dicussed.
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  • 61
    ISSN: 1432-2013
    Keywords: Cytochromes ; Kidney ; Enzyme Induction ; Aldosterone ; Adrenalectomy ; Cytochrome ; Niere ; Enzyminduktion ; Aldosteron ; Adrenalektomie
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The influence of aldosterone in vivo on cytochromes in rat kidney mitochondria is studied, comparing rats in normal state, adrenalectomized state, and adrenalectomized rats 2 hours after administration of adlosterone (7.5 μg per 100 g rat as single dose plus infusion of 0.125 μg per hour and 100 g rat). No significant changes between these states are observed of either cytochrome b, cytochrome c1, or cytochrome c content. Cytochrome a, as estimated from the 605 mμ band of the difference spectrum (reduced vs. oxidized), decreases from 508±51 nanomoles per g protein (n=12) in the controls to 273±65 (n=12) nanomoles per g protein in the adrenalectomized state. After administration of aldosterone to adrenalectomized rats the concentration of cytochrome a increased to 464±38 nanomoles per g protein (n=12). The difference spectrum (anaerob vs aerob+Antimycin A) shows that the absorbancy maximum at 444 mμ (more specific for cytochrome a3) is also considerably decreased after adrenalectomy, and increased after administration of aldosterone to adrenalectomized rats. Hence the contents of both compounds of cytochrome oxidase, cytochrome a and cytochrome a3, appear to be controlled by aldosterone. The molar ratio of cytochrome c to cytochrome a is 1.1 in the controls, 1.8 after adrenalectomy, and 1.1 after administration of aldosterone to adrenalectomized rats. Possible relations of this effect to the previously observed increase of tricarboxylic acid cycle enzyme activities under aldosterone are discussed. The 46% decrease of the cytochrome a content in mitochondria from the whole kidney of adrenalectomized rats, which is restored to the normal level in response to aldosterone, is difficult to reconcile with the concept that the hormone acts on distal tubules only, as these constitute only about 10% of the material used. Therefore, the present result is considered to support the concept that the hormone acts on both distal and proximal tubules.
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  • 62
    ISSN: 1432-2013
    Keywords: Kidney ; Concentration ; Infusion ; Urea ; Electrolyts ; Niere ; Konzentrierung ; Infusion ; Harnstoff ; Elektrolyte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Zur Ermittlung der Konzentrierfähigkeit der Rattenniere für Harnstoff, NaCl und KCl und der gegenseitigen Beeinflussung dieser Stoffe bei der Bildung eines konzentrierten Harns werden jeweils 6 Ratten Verweilkatheter in Magen und Blase gelegt und über den Magenkatheter Lösungen mit linear ansteigenden Konzentrationen (250 mOsm/l pro Tag) von Harnstoff, NaCl oder KCl zugeführt und untersucht, wie hoch die Konzentrationen dieser Stoffe im Harn ansteigen. In einer ersten Versuchsreihe wird bei einer Flußgeschwindigkeit von 2 ml/h die Osmolarität eines NaCl-Harnstoff-Gemisches gesteigert und der Anteil des Harnstoffs an der Osmolarität in 6 Einzelversuchen von 0% über 20, 40, 60, 80 auf 100% variiert. Die höchsten NaCl-Konzentrationen werden bei einem Harnstoffanteil von 20%, die höchsten osmotischen Konzentrationen bei einem Harnstoffanteil von 60% und die höchsten Harnstoffkonzentrationen bei einem Harnstoffanteil von 80% erreicht. Bei 60 und 80% Harnstoffanteil überleben die Tiere die Versuche am längsten. In den weiteren Versuchsreihen wird bei Infusionsgeschwindigkeiten von 1, 2 und 4 ml/h jeweils nur die Konzentration eines Stoffes—Harnstoff, NaCl oder KCl—in der Infusionslösung linear erhöht. Diese, enthält entweder nur den Stoff, dessen Konzentration ansteigt oder zusätzlich eine konstante Konzentration von NaCl, KCl oder Harnstoff. Es zeigt sich, daß bei steigendem Harnstoffangebot die maximal erreichten Harnstoffkonzentrationen mit steigender Infusionsgeschwindigkeit im allgemeinen stark abnehmen. Die maximal erreichten Elektrolytkonzentrationen bei steigendem NaCl- oder KCl-Angebot sind dagegen nur wenig von der Infusionsgeschwindigkeit abhängig. Abweichend von dieser Regel werden bei steigendem KCl-Angebot ohne NaCl-oder Harnstoffzusatz die maximalen KCl-Konzentrationen im Urin bei einer mittleren Flußgeschwindigkeit erreicht. Auch diese Versuche zeigen, ebenso wie die erste Versuchsreihe, daß bei reinem Harnstoffangebot höhere Konzentrationen als bei reinem Elektrolytangebot und die höchsten Gesamtosmolaritäten bei gleichzeitigem Elektrolyt- und Harnstoffangebot erreicht werden.
    Notes: Summary To investigate the concentration ability of the rat kidney for urea, NaCl and KCl and their interdependence on producing concentrated urine, solutions of urea, NaCl or KCl in rising concentrations were infused into the stomachof anaenethetized rats. The urine was continously collected and analysed for these substances. In 6 series of experiments at a rate of the infusion of 2 ml/h the osmolarity of a urea-NaCl mixture was raised, whereby the share of the urea in the osmolarity varied from 0% to 100% (in steps of 20%). The highest NaCl-concentration in the urine is found if the urea fraction is 20%, the highest osmotic concentration if the urea fraction is 60% and the highest urea concentration if the urea fraction is 80%. The animals survive the experiments, best if the urea fraction is 60–80%. In further series the concentration of one substance only (urea, NaCl or KCl) was raised at rates of flow of 1,2 and 4 ml/h. The infusion contained only the substance that was raised or in addition NaCl, KCl or urea at a constant concentration. With rising urea supply the maximum urea concentration decreases considerably with increasing rates of infusion, whereas if the NaCl or the KCl supply is raised the maximum electrolyte concentration is nearly independent of the flow rate. However, if KCl is the only substance that is supplied the concentration of KCl in the urine reaches a maximum at medium flow rates. The experiments show that the combined infusion of urea and electrolytes yields higher urine osmolarities than infusion of urea or electrolytes alone whereby urea raises the osmolarity more than the electrolytes.
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  • 63
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    Pflügers Archiv 316 (1970), S. 1-25 
    ISSN: 1432-2013
    Keywords: Kidney ; Sodium Transport ; Sodium Pumps ; Ethacrynic Acid ; Cardiac Glycosides ; Niere ; Natrium-Transport ; Natriumpumpen ; Etacrynsäure ; Herzglykosiden
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cells from guinea pig kidney cortex slices, which have been loaded with Na and caused to lose K, by leaching at 0.6° C for 2.5 hours, extrude Na with Cl upon rewarming to 25° C in a medium without K. A subsequent rise in the K concentration in the bath at 25° C induces further net Na extrusion, 1 Na being extruded in exchange for 1 K that is taken up. When the leached tissue is rewarmed to 25°C in the presence of K in the bathing fluid (2 or 16 mM), some Na is extruded accompanied with Cl (by a mechanism that is inhibited by ethacrynic acid) and some Na is extruded maintanining a 1:1 ratio with the K that is taken up, (this system being inhibited by ouabain). Thus two modes of Na extrusion are observed, mode A that is accompanied by net Cl efflux, and that is inhibited by 2 mM ethacrynic acid, but not by 1 or 10 mM ouabain and mode B in which one K is taken up for each Na extruded. Mode B is inhibited by 1 mM ouabain and not by ethacrynic acid. DNP and anoxia inhibit both modes A and B. Insufficient doses of ouabain do not explain the refractoriness of mode A to ouabain. Ouabain and ethacrynic acid are known inhibitors of the Na−K-ATPase at much lower doses. It is concluded that both modes may originate in different Na pumps which may have different energy sources. Pump A should be efficient in the volume regulation of the cell. According to experimental procedure, both modes of Na extrusion appear of comparable magnitude. In the steady-state their relative role may be different.
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  • 64
    ISSN: 1432-5233
    Keywords: Diabetes ; Duodenum ; Kidney ; Pancreas ; Rejection ; Transplant
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Il a été mis au point une méthode de laboratoire pour l'allogreffe pancréatico-duodénale chez le chien pancréatectomisé. Les animaux chez lesquels de telles greffes ont été pratiquées ont survecu plusieurs mois, si on les a traités avec azathioprine et prednisone afin de prévenir le rejet. Contrairement à ce que l'on pense généralement, le pancréas n'est pas particulièrement sensible à l'ischémie totale, étant donné qu'il y a été possible de conserverin vitro jusqu'à 24 heures d'allogreffes pancréatico-duodénales, en employant uniquement l'hypothermie et l'hyperbarie. Ces blocs pancréatico-duodénaux conservés ont été en suite allograffés chez des chiens pancréatectomisés, en obtenant la survie des animaux durant de longues périodes. Nous venons de pratiquer une allogreffe pancréatico-duodénale chez des malades avec diabète juvénile et insuffisance rénale. Parmi ces sujets, 9 ont reçu en même temps une allogreffe rénale prélevée du cadavre. Chez tous ces patients, sauf un, le pancréas a fonctionné immédiatement. Cette exception est représentée par un sujet qui a reçu une allogreffe pancréatico-duodénale prélevée du cadavre après avoir subi une ischémie irréversible. Bien que deux patients seulement soient actuellement en vie (maximum depuis onze mois), nous n'avons jamais observé de signes de rejet du pancréas. Dans 7 cas sur 8 la morte était due à complications en rapport avec l'allogreffe rénale de cadavre, tandis que chez un patient seulement l'allogreffe pancréatico-duodénale était la cause du décès. Ce malade est mort sept mois après l'intervention à cause d'une perforation aiguë du duodénum greffé. De ces recherches il résulte évident que l'antigénicité du pancréas est très inférieure à celle du rein et probablement à celle de bien d'autres organes. L'allogreffe pancréatico-duodénale isolée est actuellement projetée pour les diabétiques juvéniles avec néphropathie grave mais non terminale. Si la vasculopathie caractéristique du diabète sera modifiée par une allogreffe de pancréas, cela deviendra alors une procédure de transplantation d'exécution courante.
    Abstract: Resumen Se ha preparado en el ámbito experimental de laboratorio un procedimiento de alotrasplante pancreático-duodenal en perros operados de pancreactomía. Los perros sometidos a trasplante, y tratados después con azatioprina y prednisón para prevenir el rechazo, sobrevivieron durante muchos meses. Al revés de lo que habitualmente se opina, el pancreas no es particularmente sensible a la isquemia total, puesto que ha sido posible conservarin vitro hasta 24 horas un alotrasplante pancreático-duodenal empleando solamente la hipotermia y hiperbaria. Esos bloques pancreático-duodenales conservados, han sido después alotrasplantados en perros operados de pancreactomía consiguiendo la supervivencia de los perros durante largos periodos de tiempo. Hemos efectuado también un alotrasplante pancreático-duodenal en diez pacientes con diabetes juvenil e insuficiencia renal. Nueve de esos pacientes recibieron simultaneamente un alotrasplante renal extraido del mismo cadáver. En todos estos pacientes, menos en uno, el pancreas ha funcionado inmediatamente. La mencionada excepción la constituye un paciente que recibió un alotrasplante pancreático-duodenal procedente de un cadáver, después de haber sufrido una isquemia irreversible. Aunque solamente dos de los mencionados pacientes sigan con vida, todo lo más a los once meses, en ningún caso hemos advertido indicios de rechazo del pancreas. En siete casos de cada ocho la muerte se debió a complicaciones relacionadas con el alotrasplante renal de cadáver y sólo en uno la causa de la muerte se debió al alotrasplante pancreático-duodenal por una perforación aguda del duodeno trasplantado. De estas investigaciones se deduce con evidencia que la antigenicidad del páncreas es mucho menor que la del riñón y probablemente menor también que la de otros órganos. En la actualidad se proyecta el solo alotrasplante pancreático-duodenal para diabéticos juveniles, con nefropatía grave pero no terminal. Si la vasculopatía característica de la diabetes mellitus será modificada por el alotrasplante pancréatico, este último se convertirá en uno de los procedimientos de trasplante de ejecución más común.
    Notes: Riassunto È stato messo a punto in laboratorio un procedimento per l'allotrapianto pancreatico-duodenale nel cane pancreatectomizzato. I cani nei quali sono stati praticati questi trapianti sono sopravvissuti per molti mesi, se trattati con azatioprina e prednisone per prevenire il rigetto. Contrariamente a quanto abitualmente si ritiene, il pancreas non è particolarmente sensibile all'ischemia totale, dato che è stato possibile conservarein vitro fino a 24 ore un allotrapianto pancreatico-duodenale impiegando solamente l'ipotermia e l'iperbaria. Questi blocchi pancreatico-duodenali conservati sono stati poi allotrapiantati in cani pancreatectomizzati, ottenendo la sopravvivenza degli animali per lunghi periodi di tempo. Finora abbiamo effettuato allotrapianti pancreatico-duodenali in dieci pazienti con diabete giovanile ed insufficienza renale. Nove di questi pazienti hanno ricevuto contemporaneamente un allotrapianto renale prelevato dal medesimo cadavere. In tutti questi pazienti, tranne in uno, il pancreas ha funzionato immediatamente. Questa eccezione è rappresentata da un paziente che ricevette un allotrapianto pancreatico-duodenale da cadavere dopo aver subìto una ischemia irreversibile. Sebbene soltanto due pazienti siano attualmente in vita — uno da undici mesi —, in nessun caso abbiamo riscontrato segni di rigetto del pancreas. In sette casi su otto la morte era dovuta a complicazioni legate all'allotrapianto renale di cadavere, mentre in un paziente soltanto l'allotrapianto pancreatico-duodenale era la causa del decesso. Questo paziente morì, sette mesi dopo l'allotrapianto pancreatico-duodenale, per perforazione acuta del duodeno trapiantato. Risulta evidente da queste ricerche che l'antigenicità del pancreas è di gran lunga minore di quella del rene e, probabilmente, anche di altri organi. Il solo allotrapianto pancreatico-duodenale viene ora progettato per pazienti con diabete giovanile e nefropatia grave non in stadio terminale. Se la caratteristica vasculopatia del diabete mellito risulterà modificata per effetto dell'allotrapianto pancreatico, questo diverrà allora uno dei procedimenti di trapianto di più comune esecuzione.
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  • 65
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    Cell & tissue research 111 (1970), S. 346-363 
    ISSN: 1432-0878
    Keywords: Kidney ; Glomerulus ; Development ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Differenzierung der Podocyten wurde an Nieren 10 Tage alter Ratten raster-elektronenmikroskopisch untersucht und mit durchstrahlungs-elektronenmikroskopischen Befunden verglichen. Die Podocytenfortsätze können danach auf dreierlei Wegen gebildet werden: 1. Spalten innerhalb des Cytoplasmas lassen bandartige Cytoplasmabrücken entstehen. Diese gliedern sich weiter auf, bis zahlreiche miteinander verzahnte Fortsätze derselben Zelle entstanden sind. 2. Vom Zellrand her werden dicke Fortsätze weit vorgeschoben, die kleinere Fortsätze bilden. Durch sie können Verzahnungen mit entfernten Deckzellen entstehen. Die kleinen Fortsätze können sich jedoch auch mit anderen Fortsätzen der eigenen Zelle verzahnen. 3. Fingerförmige Fortsätze benachbarter Zellen verzahnen sich während ihrer Entstehung miteinander. Trotz zahlreicher desmosomenartiger Haftstellen zwischen benachbarten Podocyten entwickeln sich ihre Fortsätze und deren Verzahnungen anscheinend weitgehend autonom und nur selten nach den vermuteten Regeln epithelialer Nachbarschaft (Typ 3). Die Befunde sprechen vielmehr dafür, daß durchflutete und wachsende Glomerulumkapillaren die Podocytendifferenzierung induzieren und die Orientierung der Fortsätze beeinflussen.
    Notes: Summary The differentiation of the podocytes was studied by scanning electron microscopy on kidneys of 10 days old rats. The results were compared with transmission electron microscopic pictures from the same kidneys. There are three ways of forming processes by the podocytes: 1. Slits within the cytoplasm give rise to cytoplasmic bridges which further divide themselves and finally build up a meshwork of processes within a cell. 2. Thick and sometimes very long processes originate from the cell border. Their smaller branches may interdigitate with those of distant podocytes or with other processes out of the same cell. 3. Finger-like processes of neighbouring cells interdigitate as soon as they develop. In spite of numerous desmosomal structures between neighbouring podocytes the cell processes and their interdigitations develop mostly independently from each other and only seldom after the expected rules of epithelial vicinity (type 3). These findings are interpreted as indication that flooded and growing capillaries induce the differentiation of podocytes and that they influence the orientation of their processes.
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  • 66
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    Cell & tissue research 106 (1970), S. 232-250 
    ISSN: 1432-0878
    Keywords: Kidney ; Stickleback ; Mucous cells ; Action of hormones
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Pendant la période de reproduction, les néphrons du rein de l'Epinoche mâle subissent d'importantes modifications de structure sous l'action des hormones sexuelles. Au niveau de chacun d'entre eux, se différencient deux segments distincts par leur fonction et par leur cytologie. Le segment urinaire, très court, est formé de cellules identiques à celles du jeune, qui remplissent leur fonction d'excrétion. Le segment glandulaire, plus volumineux, subit une transformation muqueuse et élabore une sécrétion qui sert à construire le nid. L'évolution de ces deux segments est étudiée au cours de la période de reproduction et les modifications cytologiques correspondantes sont décrites.
    Notes: Summary Under the action of sexual hormones the nephrons of the kidney of the male three-spined-stickleback undergo considerable transformations during the breeding period. They differentiate into two segments which differ from one another in function and cytology. The cells of the urinary segment are identical to those of the young fish. They have an excretory function. The glandular segment undergoes a mucous transformation and synthesizes a secretion which is used for the building of the nest. The cytological transformations occuring at the level of these two segments during the breeding period are described with special attention to the mucous cells.
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  • 67
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    Cell & tissue research 103 (1970), S. 328-340 
    ISSN: 1432-0878
    Keywords: Kidney ; Calix ; Musculature ; Axons
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of the rat caliceal wall at its attachment to the renal parenchyma is described. Particular attention is paid to the smooth muscle cells and their associated nerves. A single overlapping layer of epithelial cells lines the renal papilla which changes abruptly to a layer of 3–5 cells where the calix gains attachment to the renal substance. In this region there is an associated increase in the underlying connective tissue which contains smooth muscle cells. These cells possess filaments, are surrounded by a basal lamina, and occur scattered among large bundles of collagen fibres. The muscle cells possess numerous branching processes as well as shorter projections which make close contacts with adjacent cells. Large numbers of axons and their associated Schwann cells are also observed in this region. The axons possess swellings, some of which lie within 800 Å of smooth muscle cells, and contain large and small granulated vesicles and agranular vesicles. They are therefore considered to be adrenergic effectors. Further out in the caliceal wall typical spindle-shaped smooth muscle cells are observed lying parallel to one another to form closely packes bundles and are associated with relatively few nerves. The significance of these observations is discussed.
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  • 68
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    Cell & tissue research 104 (1970), S. 56-68 
    ISSN: 1432-0878
    Keywords: Kidney ; Xenopus laevis ; Flask cells ; Mucopolysaccharides ; Osmotic stress
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Flaschenzellen, eigenartige flaschenförmige Epithelzellen im Verbindungsstück der Xenopusniere, enthalten ein stark entwickeltes intrazelluläres Kanalsystem, das mit sauren Mucopolysacchariden gefüllt ist. Bei Anwendung der Methode mit kolloidalem Ferriammoniumglyzerat (pH 1,6) erweisen sich das Material im Kanalsystem, in den Vesikeln in der Nachbarschaft der intrazellulären Kanäle, einige Golgi-Zisternen und Autophagosomen als positiv. Ein dichter Belag von positivem Material wurde auch an der luminalen Oberfläche der Epithelzellen des Verbindungsstückes gefunden. In Fröschen, die monatelang in Salzwasser gehalten wurden, war das intrazelluläre Kanalsystem zurückgebildet. Sein reduzierter Inhalt zeigte eine verminderte Reaktion und im Zytoplasma waren nur ausnahmsweise positiv reagierende Vesikel und Golgi-Zisternen zu beobachten. Wenn die Tiere wieder in Süßwasser gesetzt werden, kommt es zu einer Anhäufung positiver Vesikel und Golgiapparate und einer Zunahme des Materials im Kanalsystem.
    Notes: Summary “Flask cells” (Flaschenzellen), peculiar bottle-shaped epithelial cells in the intermediate segment of the Xenopus nephron, contain a highly developed intracellular channel system filled with acid mucopolysaccharides. The cells were studied with the colloidal ferriammoniumglycerate method at pH 1,6 at the electron microscopic level. The material inside the intracellular channels, cytoplasmic vesicles in the neighbourhood of the latters, several cisternae of the Golgi apparatus and some autophagosomes were found to be positive. A thick coat of positive material was observed also on the luminal surface of the epithelial cells in the intermediate segment. In frogs living in salt water for 2 months, the intracellular channels are strongly under-developed, their reduced content shows a weak reaction; positive vesicles and Golgi cisternae occur exceptionally. If the animals were returned to fresh water, an increase of the reactive vesicles and Golgi cisternae as well as the contents of the channels could be observed.
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  • 69
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    Cell & tissue research 104 (1970), S. 213-230 
    ISSN: 1432-0878
    Keywords: Kidney ; Mesonephros ; Lamprey ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of the mesonephric kidney of the lamprey, Entosphenus japonicus Martens, has been investigated with the electron microscope and discussed from the viewpoint of comparative morphology of the mesonephros. The structure of the capillary wall of the glomerulus essentially coincides with that of higher vertebrates, though its basement membrane is remarkably thick (300–400 mμ) because of a dense accumulation of fibrillar material between the endothelium and the basal lamina of epithelial cell. No obvious fenestration of the endothelial cell has been observed in the glomerulus or capillaries in any part of this organ. The kidney tubule is divided into three segments: 1. neck segment composed of ciliated cells with numerous mitochondria and glycogen particles, 2. proximal tubule composed of brush bordered cells provided with extensive pinocytotic vesicles and lysosomal granules in the apical cytoplasm and with lamellar membranes in the basal, and 3. distal tubule characterized by cells which, with their abundant mitochondria and branched tubular endoplasmic reticulum (about 500 Å diameter) with a central core, closely resemble the chloride cells in the gill filament of some teleosts. The possibility that the lamellar membranes in the proximal tubule cells correspond to basal infoldings is discussed. The extensive development of the tubular reticulum and of the mitochondria in the distal tubule cells is believed to reflect the active absorption of urine chloride in the urinary tubule of lamprey mesonephric kidney evidenced by physiologists. The proximal tubule is suggested to take a part also in the urinary transport of water and ions, as the lamellar membranes found in the cells of this portion likely correspond to the basal infoldings in more advanced forms of the kidney. The epithelial cells of the ureteric duct are characterized by granules suggesting a mucous secretion. No fine structure implying an absorptive activity in this duct has been observed.
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  • 70
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    Cell & tissue research 104 (1970), S. 240-258 
    ISSN: 1432-0878
    Keywords: Kidney ; Aglomerular ; Teleosts ; Lophius piscatorius
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of the secretory tubules in the kidney of the aglomerular goose-fish (Lophius piscatorius) is described. The cells have a pyramidal shape, are joined together by multiple desmosomes, and share as main characteristics: abundant and deep inflections of the basal and lateral cell membranes; “coated” luminal plasma membranes forming multiple microvilli or a genuine brush border; moderate numbers of comparatively small mitochondria, usually unassociated with the basal and lateral plasma membrane specializations; numerous multivesicular bodies occuring in the apical cytoplasm; abundant large lysosome-like bodies in the intermediate regions of the cytoplasm; and comparatively poor development of endoplasmic reticulum and Golgi apparatus. The observations suggest that the cells perform both absorptive and secretory functions and are metabolically unusually active in autolytic and heterolytic work. Comparisons with other aglomerular species indicate that the ability for active secretory function is not necessarily dependent on a close association between plasma membrane and mitochondria; however, this ability does appear to require a markedly increased basal and/or lateral cell surface created by multiple invaginations of the plasma membrane. The abundance of desmosomes and associated structures appears to represent a unique structural specialization of the goosefish tubule, and indicates that the cells must be firmly anchored to one another to supply a rigid and mechanically continuous lining of the tubule. The multivesicular bodies probably represent endocytic vacuoles which fuse with apical vesicles and invaginate their outer membrane to form the internal vesicles; they appear to transform to “ambilysosomes” via a function as heterophagosomes and — later — combined hetero- and autophagosomes.
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    Naunyn-Schmiedeberg's archives of pharmacology 264 (1969), S. 427-433 
    ISSN: 1432-1912
    Keywords: Sulfonamides ; Plasma Concentration ; Kidney ; Excretion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A study of the distribution of sulfadimethoxine and sulfisoxazole in plasma, kidney cortex and medullopapillary tissue is presented. Equimolar amounts of each sulfonamide were fed to separate groups of hydropenic rats, and measurements carried out after one hour and five hours. Similar plasma concentrations of either drug were encountered one hour after the ingestion. A significant increase in the plasma concentration of sulfadimethoxine and a significant decrease in the plasma concentration of sulfisoxazole were observed five hours after ingestion. There was no change in the kidney tissue/plasma concentration ratios between one and five hours after the ingestion of sulfadimethoxine or sulfisoxazole. However, the ratios were significantly higher for sulfisoxazole, a fact that can be explained by its higher renal excretion rate. Likewise, the significant higher cortico-papillary concentration gradient observed for sulfisoxazole is interpreted to be a result of its slower rate of back diffusion in the distal segments of the nephron (on account of its lower pKa) and in contrast to sulfadimethoxine to the lack of active reabsorption of sulfisoxazole.
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  • 72
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    Naunyn-Schmiedeberg's archives of pharmacology 264 (1969), S. 165-171 
    ISSN: 1432-1912
    Keywords: Mercaptans ; Kidney ; Antidiuretic Hormone ; Thiole-Niere ; Antidiuretisches Hormon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In conscious, moderately hydrated female rabbits the effect of NaCl,l-alanine,l-serine,l-cysteine, 2,3-dimercapto-1-propanol, S-(2-aminoethyl)-isothiouronium, Na2S2O3, S-methyl-l-cysteine andd-penicillamine upon renal secretion of water and osmotically active substance was investigated. All compounds, except NaCl,l-alanine andl-serine, caused a decrease of urine volume and an increase of osmolarity. The effect is similar to that of the antidiuretic hormone and is dependent upon the presence of the SH-group.
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  • 73
    ISSN: 1432-2013
    Keywords: Kidney ; Sodium ; Filtered Load ; Reabsorption Rate ; Concomitant Anion ; Niere ; Natrium ; filtered load ; Reabsorptionsrate ; Begleitanion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Zur Analyse der Bedeutung des Na+-Angebotes und des-Begleitanions für die absolute und die fraktionale Na+-Reabsorption wurden folgende Versuche an isolierten, künstlich perfundierten Nieren von Rana ridibunda durchgeführt: 1. Variation des Na+-Angebotes durch unterschiedliche NaCl-Konzentrationen in der Perfusionsflüssigkeit. 2. Variation des Na+-Angebotes durch Änderung der filtered load von Na+—als Cl− vorliegen — infolge verschiedener Einstellung der GFR durch unterschiedliche Perfusionsdrucke. 3. Bestimmung der Na+-Reabsorption bei Angebot verschiedener Na-Cyclohexansulfamat (Na-Cyclamat)-Konzentrationen, eines Na+-Salzes mit einem großen, schwer penetrierenden Anion. 4. Bestimmung der Na+-Reabsorption bei Angebot verschiedener Na+-Konzentrationen, wobei das Begleit-Anion zu 66,6% Cl− und 33,3% HCO3 − war. Die Ergebnisse sind: 1. Bei NaCl-Angebotskonzentrationen von mehr als 76,5 mMol/l steigt die Na+-Reabsorptionsrate nicht weiter an, sie bleibt auf einem Niveau stabilisiert. Die fraktionale Reabsorption ist bei niederen Na+-Angebotskonzentrationen groß, bei hohen klein. Das Phänomen der glomerulär-tubulären Balance betrifft nur einen mittleren Bereich. 2. Bei Erhöhung der filtered load von Na+ durch Erhöhung der GFR steigt die Na+-Reabsorptionsrate auf wesentlich größere Werte als bei Erhöhung der Na+-Angebotskonzentration. Steigerung der filtered load von Na+ über 32 μMol/min · kg führt nicht zu einer weiteren Steigerung der Na+-Reabsorption. Auch hier ist die glomerulär-tubuläre Balance nur für einen mittleren Bereich der filtered load gegeben. 3. Bei Na-Cyclamat-Angebotskonzentrationen über 38,25 mMol/l steigt die Na+-Reabsorptionsrate nicht weiter an, sie bleibt dann auf einem Niveau stabilisiert. Die fraktionale Na+-Reabsorption sinkt mit steigender Na-Cyclamat-Konzentration. 4. Bei Na+-Angebotskonzentrationen, wobei das Anion zu 66,6% als Cl− und zu 33,3% als HCO3 −vorliegt, von mehr als 114,75 mMol/l steigt die Na+-Reabsorptionsrate nicht weiter an; sie bleibt auf einem Niveau stabilisiert. Die fraktionale Na+-Reabsorption ist bei einer Na+-Angebotskonzentration von 76,5 mMol/l am größten. Die Na+-Reabsorptionsrate erweist sich als in starkem Maße von der filtered load von Na+ abhängig. Erhöhung der filtered load durch Erhöhung der GFR führt gegenüber den Versuchen mit Erhöhung der Na+-Angebotskonzentration zu einer wesentlich größeren Zunahme der Na+-Reabsorptionsrate. Die Na+-Reabsorption ist in allen Versuchsanordnungen — auf verschieden hohem Niveau — limitiert. Das Begleitanion des Na+ ist insofern von Bedautung für dessen Reabsorptionsrate, als bei Angebot eines großen Anions (Cyclamat) weniger Na+ transportiert wird als bei Angebot eines kleinen Anions. Die Steigerung der Na+-Reabsorptionsrate bei Anwesenheit von HCO3 − ist möglicherweise eine Folge der dadurch bedingten intracellulären Alkalisierung.
    Notes: Summary With the aim of studying the effect of the tubular Na+-load and of the type of anion on the renal Na+-reabsorption the following experiments were carried out using isolated artificially perfused kidneys of Rana ridibunda. 1. Variation of the tubular Na+-load by changing the concentration of NaCl in the perfusion fluid. 2. Variation of the tubular Na+-(Cl−)-load by changing the rate of glomerular filtration (GFR) by means of altering the perfusion pressure. 3. Determination of the rate of Na+-reabsorption if Na+ is offered in the form of Na-cyclamate, a Na+-salt with a large and slowly penetrating anion. 4. Determination of the rate of Na+-reabsorption at tubular Na+-loads consisting to 33% of NaHCO3 and to 66% of NaCl. The following results were obtained: 1. At NaCl-concentrations in the perfusion fluid above 76.5 mMol/l the rate of Na+-reabsorption remains constant. The fractional reabsorption at low Na+-concentrations is great, it is low at high Na+-concentrations. The phenomenon of glomerulo-tubular balance only applies to a medium range. 2. Raising the tubular Na+-load by increasing the GFR results in a significantly larger increase of the fractional Na+-reabsorption than does raising the tubular Na+-load by increasing the Na+-concentration. Raising the tubular Na+-load above 32 μMol/min · kg does not lead to a further increase of Na+-reabsorption. Here also glomerulo-tubular balance is maintained only within a medium range. 3. At concentrations of Na+-cyclamate above 38.25 mMol/l the rate of Na+-reabsorption remains constant. With increasing concentrations of Na+-cyclamate the fractional Na+-reabsorption decreases. 4. Above a total Na+-concentration of 114.75 mMol/l (66.6% NaCl and 33.3% NaHCO3) the rate of Na+-reabsorption remains constant. The fractional reabsorption of Na+ under these conditions reaches a maximum at a Na+-concentration of 76.5 mMol/l. The rate of Na+-reabsorption depends largely on the filtered Na+-load. However, the quantity of Na+ reabsorbed is higher if the Na+-load is raised by increasing the GFR instead of by raising the Na+-concentration in the perfusion fluid. Under all experimental conditions studied the tubular reabsorption of Na+ is limited at different but definite levels. The type of anion influences the rate of Na+-reabsorption in so far as large anions (cyclamate) decrease the reabsorption of Na+ at a given tubular Na+-load. Presumably the observed increase of Na+-reabsorption in the presence of NaHCO3 is the result of a cellular alkalinisation due to the bicarbonate.
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  • 74
    ISSN: 1432-2013
    Keywords: Kidney ; Experimental Hypertension ; Renal Blood Flow ; Renal Medullary Blood Flow ; Cortico-Medullary Gradient ; Niere ; experimenteller Hochdruck ; Nierendurchblutung ; Nierenmarkdurchbutung ; cortico-medullärer Gradient
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 4 Wochen nach Klammerung einer Nierenarterie betrug der mittlere arterielle Blutdruck 200 mm Hg. Die Aufnahme von86Rubidium, 2 min nach i.v. Injektion, wurde in der Nierenrinde und in verschiedenen Schnitten des Nierenmarks bestimmt. Gemessen mit dieser Methode war die Durchblutung der Rinde in der ungeklammerten, unter dem hohen Blutdruck stehenden Niere unverändert. Im äußeren Mark war die Durchblutung um 40% im inneren Mark um 50% und in der Papille um 70% höher als in der geklammerten Niere. Gesamtdurchblutung und regionale Durchblutung der geklammerten Niere waren statistisch nicht verschieden von Nieren normotensiver Tiere. Das Herzzeitvolumen der Hochdruck-Tiere war unverändert. Inulin- und PAH-Clearance waren in der ungeklammerten und in der geklammerten Niere normal. Die Gewebe-Osmolalität war im inneren Mark und in der Papille der ungeklammerten Niere niedriger als in der geklammerten Niere. Die Na+-Konzentration war im inneren Mark und in der Papille der ungeklammerten Niere etwas höher als in der geklammerten Niere. Die Befunde weisen darauf hin, daß beim chronischen Hochdruck keine Autoregulation der Nierenmarkdurchblutung besteht. Es wird angenommen, daß die gesteigerte Markdurchblutung für die vermehrte Harnausscheidung der ungeklammerten Niere verantwortlich ist.
    Notes: Summary Four weeks after clamping one renal artery, mean arterial blood pressure averaged 200 mm Hg.86Rubidium-uptake 2 min after intravenous injection, was measured in the renal cortex and in different slices of renal medulla. As estimated by this method, blood flow of the untouched kidney which is exposed to the high blood pressure was unchanged in the cortex. Blood flow in the outer medulla was elevated by 40%, in the inner medulla by 50% and in the papilla by 70% when compared with the clamped kidney. Total and regional blood flow of the clamped kidney was not statistically different from kidneys of normotensive controls. Cardiac output was not changed in hypertension. Inulin and PAH clearance were normal in both the untouched and in the clamped kidney. Tissue osmolality of inner medulla and papilla was lower in the untouched than in the clamped kidney. Sodium concentration in inner medulla and papilla of the untouched kidney was slightly higher than in the clamped kidney. It is concluded that in chronic hypertension, autoregulation of blood flow through the medulla is not maintained. The increased medullary blood flow may be responsible for the elevated urinary excretion of the untouched kidney in chronic hypertension.
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  • 75
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    Pflügers Archiv 313 (1969), S. 43-52 
    ISSN: 1432-2013
    Keywords: Niere ; experimenteller Hochdruck ; Glomerulumfiltrat ; Einzelnephronfiltrat ; juxtamedulläres Nephron ; Kidney ; Experimental Hypertension ; Glomerular Filtration Rate ; Single Nephron Filtration Rate ; Juxtamedullary Nephron
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary The function of juxtamedullary nephrons was investigated by micropuncture of long loops of Henle at the exposed papilla in normal rats and in the untouched kidney of rats with experimental hypertension (unilateral Goldblattclip). With increasing blood pressure (range from 90–190 mm Hg) a continuous rise in juxtamedullary single nephron glomerular filtration rate was observed. Juxtamedullary single nephron GFR averaged 60×10−6 ml/min/g K.W. in the control group (mean arterial blood pressure 116 mm Hg) and 114×10−6 ml/min/g K.W. in the hypertensive group (mean arterial blood pressure (164 mm Hg). There was no change in superficial single nephron GFR (30×10−6 ml/min/g K.W.) but a slight increase in total kidney GFR from 1.07 to 1.28 ml/min g K.W. In both the normotensive and the hypertensive animals, tubular fluid-to-plasma (TF/P) inulin ratio and intratubular flow rate in the descending limb of the long loops of Henle were not statistically different from those found in the ascending limb. Intratubular flow rate in the hypertensive rats was twice as high as in the controls; the mean TF/P inulin ratios in the two groups did not differ from each other. Appearance time of lissamine green in the long loops of Henle and in the collecting ducts was shortened in the hypertensive animals. It is concluded that there is no autoregulation of glomerular filtration rate in juxtamedullary nephrons. The increased juxtamedullary GFR may contribute to the elevated urinary excretion of the unclipped kidney in hypertensive rats.
    Notes: Zusammenfassung Untersucht wurde die Funktion der juxtamedullären Nephrone (Mikropunktion der langen Henleschen Schleifen an der freigelegten Papille) an normalen Ratten und an der ungeklammerten Niere von Ratten mit experimentellem Hochdruck (einseitige Goldblatt-Klammer). Mit steigendem Blutdruck (von 90–190 mm Hg) wurde eine kontinuierliche Zunahme des juxtamedullären Einzelnephronfiltrates beobachtet. Es betrug im Mittel 60·10−6 ml/min/g Niere bei der Kontrollgruppe (mittlerer arterieller Blutdruck 116 mm Hg) und 114·10−6 ml/min/g Niere bei der hypertensiven Gruppe (mittlerer arterieller Blutdruck 164 mm Hg). Das Einzelfiltrat oberflächlicher Nephrone änderte sich nicht; es betrug 30·10−6 ml/min/g Niere. Das Glomerulumfiltrat der gesamten Niere nahm geringfügig von 1,07 auf 1,28 ml/min/g Niere zu. Sowohl bei den normotensiven wie bei den hypertensiven Tieren waren TF/P-Inulin-Quotient und intratubuläre Stromstärke im auf- und absteigenden Schenkel der Henleschen Schleife statistisch nicht voneinander zu unterscheiden. Die intratubuläre Stromstärke war im Mittel bei den hypertensiven Tieren doppelt so hoch wie bei der Kontrollgruppe; die TF/P-Inulin-Quotienten waren in beiden Gruppen statistisch nicht voneinander verschieden. Die Ankunftszeit von Lissamingrün in den langen Henleschen Schleifen und in den Sammelrohren war bei den hypertensiven Tieren verkürzt. Die Befunde weisen darauf hin, daß keine Autoregulation des juxtamedullären Glomerulumfiltrates besteht. Es wird angenommen, daß die Erhöhung des juxtamedullären Filtrats zu der vermehrten Harnausscheidung der ungeklammerten Niere von hypertensiven Ratten beiträgt.
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  • 76
    ISSN: 1432-2013
    Keywords: Kidney ; Tubular Sodium Transport ; Sodium Pump ; Ion Transport ; Perfusion of Kidney ; Niere ; Tubulärer Natrium-Transport ; Natriumpumpe ; Ionentransport ; Nierenperfusion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Transtubular absorption of Na and Cl, and intracellular ion concentrations were evaluated in toad kidneys perfused with solutions containing K and without K, and in the presence of 1 mM Ouabain and 1 mM Ethacrynic acid. The following values were obtained with 8.5 mM K: Transtubular absorption of Na and Cl∼68% (percent of filtered load); cell content 294 μmole Na, 433 μmole K, 100 μmole Cl/g solids. Lack of K in the perfusate diminished transtubular absorption to ∼25% and the cells gain 244 μmole Na/g solids, and lose an equimolecular quantity of K. The process is reversible upon raising the K concentration in the perfusate. Ouabain inhibits transtubular absorption to ∼6%; the cells lose about 110 μmole K/g solids, but cellular Na is maintained at the control levels. Ethacrynic acid inhibits transtubular absorption to ∼3%; the cells approximately double their Na and Cl content, but their K is maintained at the control levels. These observations cannot be explained exclusively in terms of an effect on the distal tubule. Probably proximal as well as distal tubules are involved. A single Na pump seems insufficient to account for all experimental findings. The existence of two separate pumps is therefore proposed.
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  • 77
    ISSN: 1432-2013
    Keywords: Kidney ; Experimental Hypertension ; Tubular Sodium Concentration ; Tubular Potassium Concentration ; Renin ; Angiotensin ; Niere ; Experimenteller Hochdruck ; Tubuläre Natriumkonzentration ; Tubuläre Kaliumkonzentration ; Renin ; Angiotensin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 3–4 Wochen nach Klammerung einer Nierenarterie und Nephrektomie der kontralateralen Niere wurde die Wasser-, Natrium- und Kaliumresorption in den einzelnen Abschnitten des Nephrons untersucht. Die Niere war trotz der Klammerung vergrößert. Die Wasser- und Natriumausscheidung war pro Gramm Niere nicht signifikant erhöht. Das Glomerulumfiltrat und das Einzelnephronfiltrat pro Gramm Niere, die Passagezeit von Lissamingrün durch den proximalen Tubulus und durch die Henlesche Schleife, sowie die fraktionelle Wasserresorption bis zum Ende des distalen Tubulus waren normal. Im Gegensatz zu früheren Untersuchungen an der geklammerten Niere ohne kontralaterale Nephrektomie fand sich in den geklammerten Restniere ein normaler Abfall der spät distalen Natriumkonzentration und ein normaler Anstieg der Kaliumkonzentration im distalen Tubulus. Es wird angenommen, daß die Normalisierung der distalen Tubulusfunktion in der geklammerten Niere nach Nephrektomie der contralateralen Niere auf die Normalisierung des Reningehalts zurückzuführen ist. Die Versuche weisen im Zusammenhang mit anderen Befunden darauf hin, daß die intrarenale Renin- bzw. Angiotensinkonzentration einen direkten Effekt auf die Natriumresorption im distalen Tubulus ausübt, der der Aldosteronwirkung entgegengesetzt ist.
    Notes: Summary 3–4 weeks after clamping of one renal artery and nephrectomy of the contralateral kidney the reabsorption of water, sodium and potassium was studied in the different parts of the nephron. Despite clamping, the kidney was enlarged. Water and sodium excretion per g kidney was not significantly increased. Glomerular filtration rate and single nephron filtrate per g kidney, transit time of Lissamine Green through the proximal tubule and through Henle's loop and fractional water reabsorption up to the end of the distal tubule were normal. Contrary to earlier investigations on the clamped kidney without contralateral nephrectomy, there was a normal decrease of sodium concentration and a normal increase of potassium concentration along the distal tubule. We believe that the normalization of distal tubular function in the clamped kidney after nephrectomy of the contralateral kidney is due to the normalization of the renin content. It is suggested that the intrarenal renin resp. angiotensin concentration has a direct inhibitory effect on the sodium reabsorption in the distal tubule, opposite to the effect of aldosterone.
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  • 78
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    Cell & tissue research 101 (1969), S. 401-407 
    ISSN: 1432-0878
    Keywords: Myriapoda ; Kidney ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Feinstruktur der Maxillarnephridien von Scutigerella immaculata Newport mit ihren drei Abschnitten Sacculus, Tubulus und Ausführgang wurde untersucht. Die Zellen des Sacculus sind typische Podocyten, an denen eine Ultrafiltration ablaufen kann. Möglicherweise wird die Filtration durch einen den Sacculus umgebenden Muskel unterstützt. Die Zellen des Tubulus zeigen basale Einfaltungen und im proximalen Teil auch Mikrovilli. Sowohl im Tubulus als auch im Ausführgang, dessen Zellen ebenfalls basale Einfaltungen aufweisen, werden Reabsorptionsprozesse vermutet.
    Notes: Summary The fine structure of the maxillary kidney of Scutigerella immaculata Newport (Symphyla) has been investigated. It may be compared with segmental organs of other Arthropoda having an end-sac which forms a primary urine by ultrafiltration. The filtration may be supported by a muscle surrounding the end-sac. The tubular part of the nephridium and the efferent duct show structures which may be involved in reabsorption.
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  • 79
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    Cell & tissue research 102 (1969), S. 273-282 
    ISSN: 1432-0878
    Keywords: Kidney ; Glycogen ; Mucopolysaccharides ; Diuresis ; Antidiuretic hormone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Tritiated glucose has been injected into rabbits in various states of hydration. The renal papilla of all animals showed an uptake of the label, converted into glycogen, and into mucopolysaccharides, in a manner dependent on the water balance of the animal. In papillae of control animals, the glycogen of the collecting duct epithelial cells and the mucopolysaccharides of the interstitium were labelled. In papillae of animals in an aqueous diuresis, the collecting duct glycogen was lightly labelled and there was no label over the interstitium. Antidiuretic hormone caused a diversion of label from the collecting ducts into interstitial mucopolysaccharides. The significance of these findings, with respect to renal concentrating ability, is discussed.
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  • 80
    ISSN: 1432-2013
    Keywords: Kidney ; Aldosterone ; Tubular Sodium Reabsorption ; Proximal Tubule ; Sodium Chloride Loading ; Niere ; Aldosteron ; tubuläre Natriumresorption ; proximaler Tubulus ; Natriumchloridbelastung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Ratten erhielten 4 Wochen lang isotone Kochsalzlösung als Trinkflüssigkeit. Glomerulumfiltrat und Passagezeit von Lissamin-Grün im proximalen Tubulus blieben unverändert. Die spezifische Resorptionskapazität des Tubulusepithels — gemessen mit der „gespaltenen-Tropfen-Methode“ — nahm signifikant ab. Daraus ergab sich eine Verminderung der fraktionellen Natrium-und Wasserresorption im proximalen Tubulus von 51 auf 38% der gefilterten Menge. Die Na+-Ausscheidung stieg von 0,06 (Kontrollen) auf 1,25% der gefilterten Menge. Diese Veränderungen waren rückgängig zu machen durch Injektion von d-Aldosteron. Durch Bestimmung des TF/P-Inulin-Quotienten am Ende des proximalen Konvolutes wurden die Ergebnisse bestätigt. Es wird angenommen, daß die Resorptionshemmung im proximalen Tubulus bei chronischer Kochsalzbelastung durch verminderte Sekretion von Mineralocorticoiden bedingt und letzten Endes Ursache der vermehrten Na+-Ausscheidung ist. Ein Teil der proximalen Resorptionshemmung wird anscheinend in weiter distal gelegenen Nephron-Abschnitten kompensiert.
    Notes: Summary Rats were kept on isotonic saline as drinking fluid for a period of 4 weeks. Glomerular filtration rate and proximal transit time of Lissamine green remained unchanged. The intrinsic reabsorptive capacity of the proximal tubular epithelium—measured by the “shrinking-droplet-method”—decreased significantly. As a result, fractional proximal reabsorption of sodium and water decreased from 51 to 38 per cent of the filtered load. Sodium excretion rose from 0.06 (controls) to 1,25 per cent of the filtered load. These changes were reversible by injection of d-aldosterone. The results were confirmed by measuring the TF/P ratio of inulin at the end of the proximal convolution. The results indicate that in rats chronically loaded with salt, the inhibition of fractional proximal reabsorption is due to a decreased secretion of mineralocorticoids, and is the cause of the higher sodium excretion. Apparently, the decreased proximal reabsorption is partly compensated in more distal parts of the nephron.
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  • 81
    ISSN: 1432-2013
    Keywords: Kidney ; Concentration ; Dialysis ; Urea ; Electrolytes ; Niere ; Konzentrierung ; Dialyse ; Harnstoff ; Elektrolyte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Um den Einfluß des Plasmaharnstoffspiegels auf die Konzentrierfähigkeit der Niere zu untersuchen, wird der Blutkreislauf von Ratten an eine Dialysiervorrichtung angeschlossen und der Harnstoffspiegel des Blutes für 3 Std durch Dialyse gegen eine harnstoffreie Spüllösung gesenkt. Gleichzeitig wird der Harnfluß der Tiere durch eine Regelanordnung konstant gehalten. Die Regelung wird dadurch erreicht, daß dem Blutkreislauf bei zu hohem Harnfluß automatisch Flüssigkeit entzogen und bei zu niedrigem Harnfluß Flüssigkeit zugeführt wird. Es wird gefunden, daß die Harnstoffkonzentrationen im Harn linear mit dem Plasmaharnstoffspiegel abfallen bzw. ansteigen. Die Summe der Elektrolytkonzentrationen fällt dagegen mit dem Plasmaharnstoffspiegel nur wenig ab. Falls ein völliger Harnstoffentzug möglich wäre, würde auch dann noch eine Konzentrierung der Elektrolyte auf mehr als doppelt isoton möglich sein. Die Ergebnisse der Untersuchung lassen sich am einfachsten mit der Annahme interpretieren, daß in der Niere der Ratte zwei unterschiedlich arbeitende Konzentrierungsmechanismen wirksam sind, von denen der eine im wesentlichen Elektrolyte, der andere im wesentlichen Harnstoff konzentriert. Der Konzentrierungsmechanismus für Elektrolyte könnte im äußeren Mark, der für Harnstoff im inneren Mark lokalisiert sein.
    Notes: Summary To investigate the influence of plasma urea levels on the concentrating power of the kidney, the blood circulation of rats was connected to a dialyser; with dialysis against a urea-free cleaning solution, the urea level of the blood was lowered for three hours. During this, the urine flow of the animals was kept constant by a regulating arrangement. This control was achieved by removing fluid from the blood circulation in the case of too high urine flow and by putting in fluid in the case of too low urine flow. It was found that the concentration of urea in the urine had a direct linear relationship with the plasma urea level. The total electrolyte concentration fell only slightly compared to the plasma urea level falls. If the urea could have been completely removed, high concentrating of the electrolyte, to more than double isotonic, would still have been possible. The simplest way to interpret the results of this research is by the hypothesis that two different concentrating mechanisms are at work in the rat kidney, the one essentially concentrating electrolytes, and the other principally urea. The concentrating mechanism for electrolytes could be localised in the outer medulla, and for urea in the inner medulla.
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  • 82
    ISSN: 1432-2013
    Keywords: Kidney ; Concentration ; Infusion ; Urea ; Electrolytes ; Niere ; Konzentrierung ; Infusion ; Harnstoff ; Elektrolyte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Um die gegenseitige Beeinflussung von Harnstoff und NaCl bei der Bildung eines konzentrierten Harns zu untersuchen, werden Ratten 2 Tage lang NaCl-Lösungen mit wechselndem Harnstoffgehalt infundiert. Sodann werden der Harn sowie das Gewebe der Nierenrinde, des äußeren Marks und des inneren Marks auf ihren Gehalt an Kalium, Natrium und Harnstoff analysiert. Es wird gefunden, daß die Konzentrierfähigkeit der Rattenniere unter diesen Versuchsbedingungen für NaCl bei gleichzeitiger Zufuhr von Harnstoff geringer wird. In der Niere steigen NaCl und Harnstoffkonzentrationen unter allen Infusionsbedingungen von der Nierenrinde zur Nierenpapille hin an. Bei Infusion reiner NaCl-Lösungen entsprechen die NaCl- und Harnstoffkonzentrationen im Harn denen in der Papille. Bei Infusion von harnstoffhaltigen NaCl-Lösungen sind im Harn die NaCl-Konzentrationen höher und die Harnstoffkonzentrationen niedriger als im Papillengewebe. Diese Ergebnisse schließen aus, daß die hohen Harnstoffkonzentrationen im Nierenmarkgewebe durch einfache Diffusion des Harnstoffes aus den Sammelrohren in das Nierenmarkgewebe zustande kommen. Es wird die Möglichkeit diskutiert, daß die Harnstoffkonzentrierung unter den hier wiedergegebenen Versuchsbedingungen durch Gegenstromdiffusion in dem Vasa recta-System verursacht wird. Der Konzentriereffekt hierfür könnte durch einen Wasserfluß aufgrund osmotischer Kräfte von dem Blutgefäßsystem in die Henleschen Schleifen zustande kommen, wenn der Harn in den Henleschen Schleifen durch Aufnahme von NaCl, das aus den Sammelrohren stammt, hyperton wird.
    Notes: Summary To investigate the mutual interdependence of urea and sodium in producing concentrated urine, solutions of different concentrations of sodium and urea were infused into the stomach of rats. After two days' infusion, the urine and tissues from the different zones of the kidneys were analysed for sodium, potassium and urea content. It was found that the efficiency of the rat kidney in producing urine with high sodium content was diminished if urea was infused together with the sodium chloride. Under all conditions sodium and urea concentrations increased from the cortex to the papilla of the kidneys. When pure sodium chloride solutions were infused, sodium and urea concentrations in the urine were nearly equal to the corresponding concentrations in the papilla. Infusion of solutions containing NaCl and urea caused production of urine with a higher sodium concentration and lower urea concentration than in the papilla. These results show that the high concentration of urea in the medulla of the kidney does not arise by passives diffusion of urea from the collecting ducts into the medullary tissue. The possibility that the concentration of urea in the inner medulla is produced by counter current diffusion of urea in the vasa recta is discussed. The concentration effect necessary for this counter current multiplication could be created by an osmotic flow of water from the vasa recta into loops of Henle, if the urine in the loops becomes hypertonic by taking up sodium chloride from the collecting ducts.
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  • 83
    ISSN: 1432-2013
    Keywords: Tubules ; Kidney ; Intraluminal Oil Injection ; Ultrastructure of Kidney ; Proximales Tubuluskonvolut ; Rattenniere ; intraluminale Ölinjektion ; Ultrastruktur der Niere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Light- and electronmicroscopic evaluation of proximal convolutions of the rat kidney were made following injection with either mineral oil or castor oil. The following observations were made: 1. Injection of mineral oil does not result in a complete blockade of the tubular lumen and leads to morphological lesions of epithelial cells. 2. Injection of the more viscous castor oil, in contrast, leads to a dilatation of the tubular lumen and a compression of the brush border of proximal tubular cells. Thus a better blockade of longitudinal flow is achieved. A toxic effect of castor oil on the tubular epithelium could not be detected. Mechanical lesions, similar to those observed after mineral oil injection, were less frequent. They consisted in a penetration of oil into the cells, perhaps as consequence of the tubular dilatation. 3. In oil-injected proximal tubular segments the following cytologic phenomena were observed: a) a cessation of the normal pinocytosis, which is induced in the presence of tubular fluid, b) simultaneously the “large resorption vacuoles” disappear, indicating that they originate from confluence of pinocytotic vesicles, c) in dilated tubules protein resorption vacuoles are found to have ruptured towards the tubular lumen suggesting a high hydrostatic pressure within the vacuoles.
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  • 84
    ISSN: 1432-2013
    Keywords: Kidney ; Experimental Hypertension ; Tubular Sodium Reabsorption ; Tubular Water Reabsorption ; Henle's Loop ; Niere ; experimenteller Hochdruck ; tubuläre Natriumresorption ; tubuläre Wasserresorption ; Henlesche Schleife
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 4 Wochen nach Klammerung einer Nierenarterie war der Perfusionsdruck der geklammerten Niere normal, während der arterielle Mitteldruck auf 188 mm Hg angestiegen war. Die Ausscheidung von Natrium und Wasser im Harn der geklammerten Niere war normal, im Harn der ungeklammerten Niere erheblich höher als normal. Glomerulumfiltrat (pro g Niere), intratubulärer Druck, Tubulusweite, Passagezeit von Lissamingrün und die fraktionelle Resorption von Natrium und Wasser waren im proximalen Tubulus sowohl in der geklammerten wie in der ungeklammerten Niere normal. In der ungeklammerten Niere war die Passagezeit durch die Henlesche Schleife stark verkürzt und die Resorption von Natrium und Wasser in der Schleife erheblich vermindert. Diese Veränderungen — obwohl zum Teil kompensiert durch vermehrte Resorption im distalen Tubulus und im Sammelrohr — sind verantwortlich für die höhere Wasser- und Natriumausscheidung der ungeklammerten Niere. Die Ursache ist wahrscheinlich eine stärkere Durchblutung des Nierenmarkes. Im Nephron der geklammerten Niere war die fraktionelle Natrium- und Wasserresorption nicht signifikant von normalen Werten verschieden mit der Ausnahme einer niedrigeren Natriumresorption im distalen Tubulus und einer höheren Natriumresorption im Sammelrohr. Der Natrium-Transport im distalen Tubulus ist anscheinend gestört; TF/P−Na+ betrug im Mittel 0,6 bis zum Ende des distalen Tubulus. Die Ergebnisse können die unterschiedliche Harnausscheidung erklären, die beim Hypertoniker mit einseitiger Nierenarterienstenose beobachtet wird (Howard-Test).
    Notes: Summary Four weeks after clamping one renal artery, the perfusion pressure of the clamped kidney was normal whereas the mean arterial pressure had increased to 188 mm Hg. Urinary excretion of sodium and water of the clamped kidney had not changed while that of the untouched kidney increased considerably. Glomerular filtration rate (per g kidney), intratubular pressure, tubular diameter, transit time of Lissamine green and fractional sodium and water reabsorption of the proximal tubule were normal in both the clamped and the untouched kidney. In the untouched kidney, the transit time through Henle's loop was shortened and the sodium and water reabsorption in it was significantly reduced. These changes, although partly compensated by higher reabsorption in the distal tubule and collecting duct, are responsible for the increased sodium and water excretion of the untouched kidney. They are probably due to an increased medullary blood flow. In the clamped kidney, fractional sodium and water reabsorption of the whole nephron did not differ significantly from normal values. However, sodium reabsorption was lower in the distal tubule and higher in the collecting duct. Sodium transport in the distal tubule seemed to be impaired; throughout its length sodium TF/P ratio averaged 0.6. These results may explain the different urinary excretion found in human hypertension following unilateral renal artery stenosis (Howard-Test).
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  • 85
    ISSN: 1432-2013
    Keywords: Kidney ; Fluxes ; Osmotic Gradients ; Niere ; Flüssigkeits-Substanzbewegungen ; osmotische Gradienten
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Durch artifizielle osmotische Druckdifferenzen von 150 mOsmol/l zwischen Lumen- und Blutseite der Tubulusepithelien von Rana ridibunda wird Flüssigkeit im Richtungssinne der Reabsorption oder — in geringerem Maße — der Sekretion längs des osmotischen Gradienten bewegt. Na+ wird in jedem Fall „trocken” reabsorbiert. Bei mit Furosemid blockiertem aktiven Na+-Transport läuft isoton Flüssigkeit längs des osmotischen Gradienten aus dem Tubuluslumen in das blutseitige Medium. Bei umgekehrt gerichtetem Gradienten wird das Filtrat so verändert, als ob es durch Einstrom reinen Wassers verdünnt würde. Die Tubulusepithelien verhalten sich so, als besäßen sie — im Zustand des blockierten aktiven Na+-Transportes — ein „Rückschlagventil” für Na+. Wenn der osmotische Gradient so gerichtet ist, daß Wasser oder Flüssigkeit aus dem Lumen in das blutseitige Medium läuft, dann kommt es bei umgekehrt gerichtetem Na+-Konzentrationsgradienten nicht zum Einstrom von Na+ in das Tubuluslumen. Die Na+-Harnkonzentration sinkt beträchtlich unter die des Perfusates, was als Ausdruck einer Na+-Reabsorption gegen den Konzentrationsgradienten gedeutet wird. Bei Blockierung des Na+-Transportes durch Furosemid kommt es wiederum zum Einstrom reinen Wassers in die Tubuluslumina. Die Versuche mit durch Furosemid blockiertem Na+-Transportmechanismus sind beweisend, daß die Tubuli für Na+ im Richtungssinne der Sekretion impermeabel sind. Die „Verdünnung” des Tubulusinhaltes durch einen osmotischen Gradienten, der Wasser in die Tubuli hineinlaufen läßt, kommt also nicht durch ein Überwiegen der Reabsorption über die „Sekretion” zustande. Wird statt des leicht penetrierenden Na-Chlorids das schwer penetrierende Natriumcyclohexansulfamat angeboten, dann wird absolut gegenüber den Versuchen mit Na-Chlorid weniger Na+ transportiert. Im übrigen zeigen die Nieren jedoch das gleiche Verhalten wie bei Angebot von Na-Chlorid.
    Notes: Summary Osmotic gradients of 150 mosmol/l between intratubular fluid and blood in the kidney of Rana ridibunda induce a fluid movement down the osmotic gradient which is stronger into the tubule than out of it. In either case Na+ is reabsorbed “dry”. If the active Na+-transport is blocked by Furosemid an osmotically downhill movement of isotonic fluid out of the tubule obtains. Reversal of the osmotic gradient induces a reversal of flow but the inward moving fluid is diluted. The tubular cells seem to inhibit the backwash of Na+. If the osmotic gradient induces an outflow of fluid out of the tubule no influx of Na+ occurs even in the presence of a concentration gradient for Na+ in the opposite direction. The Na+-concentration in the urine falls considerably below that of the perfusion fluid. This finding indicates Na+-reabsorption against a concentration gradient. Upon blocking of the Na+-transport by Furosemid water enters the tubules. The results of the experiments in which the Na+-transport was blocked by Furosemid prove that the tubules are impermeable for Na+ in the direction of secretion. The “dilution” of the tubular fluid as a result of an osmotic gradient which induces an influx of water isnot due to a reabsorption outbalancing “secretion”. If instead of the easily penetrating NaCl the slowly penetrating Na+-cyclohexanesulphamate is used, less Na+ is transported. However, in every other respect the results obtained are similar to those described above.
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  • 86
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    Pflügers Archiv 304 (1968), S. 336-350 
    ISSN: 1432-2013
    Keywords: Kidney ; Experimental Hypertension ; Distal Tubular Sodium Reabsorption ; Distal Osmolality ; Tubular Potassium Secretion ; Niere ; experimenteller Hochdruck ; distale Natrium resorption ; distale Osmolalität ; tubuläre Kaliumsekretion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Vier Wochen nach Klammerung einer Nierenarterie wurde die Funktion des distalen Tubulus untersucht. In der ungeklammerten, unter dem hohen Blutdruck stehenden Niere blieb die Tubulusflüssigkeit bis 90% distaler Tubuluslänge hypoton. Dies wird auf eine erhöhten Flüssigkeitseinstrom aus der Henleschen Schleife zurückgeführt; eine verminderte Wasserpermeabilität des distalen Tubulus konnte nicht nachgewiesen werden. In der geklammerten Niere war mit Ausnahme des frühdistalen Abschnittes die Natriumkonzentration on jeder Stelle des distalen Konvolutes signifikant höher als in der ungeklammerten Niere und in Kontrollnieren. Auch fehlte im distalen Tubulus der geklammerten Niere eine Nettokaliumsekretion. die distale Gleichgewichtskonzentration für Natrium war auf der geklammerten Seite erhöht, auf der ungeklammerten Seite normal. Der isotone Natriumausstrom (Methode des gespaltenen Tropfens) war in der geklammerten Niere vermindert, in der ungeklammerten Niere erhöht. Die frühdistale Harnstoffkonzentration war in der ungeklammerten Niere gegenüber der geklammerten Niere und Nieren von Kontrollratten erniedrigt. Spätdistal war TF/P-Harnstoff in beiden Nieren gleich. Beide Nieren hatten ein normales Glomerulumfiltrat und normale tubuläre Passagezeiten mit Ausnahme einer verkürzten Schleifenzeit in der ungeklammerten Niere. Die Befunde werden dahingehend interpretiert, daß der aktive Natriumtransport im distalen Tubulus der beiden Nieren voneinander verschieden ist, möglicherweise infolge des unterschiedlichen Reningehaltes der beiden Nieren.
    Notes: Summary Four weeks after constricting one renal artery distal tubular function was studied using the micropuncture technique. In the untouched kidney tubular fluid remained hypotonic up to 90% distal tubular length. We believe this to be the result of the high inflow of tubular fluid from Henle's loop. A reduced permeability for water could not be demonstrated. Except for the early part of the distal tubule there was a marked increase in sodium concentration in the clamped kidney as compared to values obtained in the untouched one and in kindneys of control animals. In addition no potassium secretion could be observed in the clamped kidney. The distal steadystate concentration for sodium was increased in the clamped kidney and normal in the untouched one. Reabsorptive half-time, measured by the split droplet technique, was prolonged in the clamped kidney and shortened in the untouched one. Early distal urea concentration was lower in the untouched kidney than in the clamped one and in control kidneys, while at the end of the distal tubule urea concentrations did not differ significantly. Both kidneys had normal glomerular filtration rates and proximal tubular transit times, whereas a shortened transit time through Henle's loop of the untouched kidney was found. The results indicate that active sodium transport in the distal tubule of the clamped kidney differs from that of the untouched one, possibly due to the different renin concentration in both kidneys.
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  • 87
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    Pflügers Archiv 305 (1968), S. 96-104 
    ISSN: 1432-2013
    Keywords: Blood Circulation Time ; Kidney ; Plasma ; Radioautography ; Radioisotope Dilution Technique ; Regional Blood Flow ; Mittlere Kreislaufzeit ; Niere ; Plasma ; Autoradiographie ; Isotopenverdünnungstechnik ; Regionale Nierendurchblutung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary At different times after injection into the renal artery of131I-albumin, the distribution of the tracer in kidneys of the rabbit and the dog was illustrated by a series of autoradiograms. In order to determine the mean circulation time for albumin in the kidney, the radioactivity over the kidney was simultaneously registered by external monitoring. A short mean circulation time was measured for albumin (plasma) passing cortex, and a longer one for that fraction of the albumin that passed through medulla, papillae, and capsule. The investigation rendered probable that the mean circulation time for blood through the kidney determined by the external technique applies to blood passing cortex. The circulation times for blood through medulla, papillae, and capsule are not included in the calculation of the mean circulation time.
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  • 88
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    Archives of toxicology 23 (1968), S. 245-249 
    ISSN: 1432-0738
    Keywords: Bone ; Strontium poisoning ; Parathormone ; Kidney ; Knochen ; Strontiumvergiftung ; Parathormon ; Niere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Restitution des strontiumgeschädigten Skelets wachsender Sprague Dawley Ratten ist von einem Anstieg der dialysablen Strontium- und Calciumfraktion des Serums begleitet. Die Ergebnisse legen eine Beeinflussung der renalen Manipulation von Kationen bei Knochenschädigungen durch Fremdmetalle nahe.
    Notes: Summary Restitution of skeletal damage caused by strontium in growing Sprague Dawley rats is accompanied by an increase in the dialysable serum fractions of strontium and calcium. The results suggest that the renal manipulation of cations is influenced in bone lesions caused by foreign metals.
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  • 89
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    Clinical and experimental medicine 145 (1968), S. 270-277 
    ISSN: 1591-9528
    Keywords: Aldosterone ; Kidney ; Stop flow dog ; Aldosteron ; Niere ; Stop flow-Hund
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Mit Stop flow-Versuchen an Hunden konnten wir nach Infusion von 1,2-3H-18-Aldosteronglucuronid im Gegensatz zur Infusion von freiem 1,2-3H-Aldosteron keine proximale Sekretion von 1,2-3H-18-Aldosteronglucuronid nachweisen. Daraus kann geschlossen werden, daß in Hundenieren die proximalen Tubuluszellen wohl 18-Aldosteronglucuronid aus Aldosteron bilden und an das Tubuluslumen abgeben, während im Nierenarterienblut vorhandenes 18-Aldosteronglucuronid nur glomerulär filtriert und ausgeschieden wird.
    Notes: Summary In stop flow experiments during infusion of 1,2-3H-18-aldosterone glucuronide there was no proximal tubular secretion of this metabolite in contrary to experiments during infusion of 1,2-3H-aldosterone. The discrepancy must be explained by formation of 1,2-3H-aldosterone glucuronide out of3H-aldosterone in proximal tubular cells, while the 1,2-3H-18-aldosterone glucuronide in the plasma of the renal artery blood is only filtered in the glomerulum.
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  • 90
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    Clinical and experimental medicine 146 (1968), S. 336-345 
    ISSN: 1591-9528
    Keywords: Aldosterone ; Kidney ; Man ; Aldosteron ; Niere ; Mensch
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Auf Grund eines Vergleiches der Verhältnisse von 1,2-3HTetrahydroaldosteronglucuronid zu 1,2-3H-18-Aldosteronglucuronid im Plasma von drei Normalpersonen und zwei nephrektomierten Patienten nach einer Injektion von 1,2-3H-Aldosteron haben wir folgende Schlüsse in Betracht gezogen: 1. Das im Blutplasma vorhandene 1,2-3H-18-Aldosteronglucuronid wird nur glomerular filtriert. 2. Die renale Clearance von 18-Aldosteronglucuronid, die etwa das Fünffache der Inulinclearance beträgt [13, 15], mu\ zu vier Fünfteln auf Bildung von 18-Aldosteronglucuronid durch die proximalen [15] Tubuluszellen zurückgeführt werden. 3. Das Ausma\ der renalen Bildung von 18-Aldosteronglucuronid liegt in einer Grö\enordnung von 80% der Gesamtmenge 18-Aldosteronglucuronid im 24 StdUrin.
    Notes: Summary After an intravenous injection of 1,2-3H-aldosterone the ratios of 1,23H-tetrahydroaldosterone glucuronide to 1,2-3H-aldosterone glucuronide in the blood plasma of three normal and two nephrectomized persons were compared. In the three normal persons the ratios were of the same magnitude as in the two nephrectomized persons. On the basis of glomerular filtration of tetrahydroaldosterone glucuronide, as previously demonstrated by renal clearance studies in man [13, 15] and stop flow experiments in dogs [6], we made the following deductions: 1. 18aldosterone glucuronide in blood plasma is only filtered in the glomerulum. 2. The renal clearance of 18-aldosterone glucuronide, as investigated during aldosterone infusion in man [13, 15], therefore must be explained by glomerular filtration of only one fifth and by formation of four fifth of 18-aldosterone glucuronide by proximal [15] tubular cells. 3. This means that about 80% of 18-aldosterone glucuronide excreted in urine is formed by the kidneys.
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  • 91
    ISSN: 1591-9528
    Keywords: Plasma FFA composition ; Individual FFA extraction in heart ; Skeletal muscle ; Kidney ; Plasma-FFS-Zusammensetzung ; Extraktion der Einzel-FFS in Herz ; Skeletmuskel ; Niere
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei narkotisierten Hunden wurden die arteriovenösen Differenzen der gesamten und der einzelnen freien Fettsäuren (FFS) am Herzen, am elektrisch stimulierten Skeletmuskel (M. gastrocnemius) und an der Niere bei verschieden hoher arterieller FFS-Konzentration untersucht. Die Konzentration der gesamten FFS wurde titrimetrisch, ihre Zusammensetzung wurde gaschromatographisch bestimmt. Bei einer Steigerung der FFS-Konzentration durch Noradrenalininfusionen stiegen die Anteile der öl- und der Palmitinsäure an, und die Anteile der Stearin- und der Linolsäure sanken ab. Bei einer Senkung der FFS-Konzentration durch Glucoseinfusionen nahmen die Anteile der öl- und der Palmitoleinsäure ab, und die Anteile der Palmitin- und der Stearinsäure nahmen zu. Unter Kontrollbedingungen entfielen am Herzen 44% der gesamten FFS-Extraktion auf die öl- und 24% auf die Palmitinsäure, am Skeletmuskel entfielen 43% auf die öl- und 29% auf die Palmitinsäure. Bei einer Steigerung der arteriellen FFS-Konzentration durch Noradrenalin extrahierten Herz- und Skeletmuskel nur noch öl-, Palmitin- und Palmitoleinsäure. Gleichzeitig wurde im Herz Stearin- und Linolsäure und im Skeletmuskel Stearinsäure produziert. In der Niere entfielen unter Kontrollbedingungen je 40% der Gesamt-FFS-Extraktion auf die Palmitin- und die ölsäure. Es wird gefolgert, daß die öl-, die Palmitin- und die Palmitoleinsäure gegenüber den anderen FFS bevorzugt als Energiequellen benutzt werden, weil bei gleicher arterieller Konzentration höhere Extraktionen für diese drei FFS gemessen wurden. Noradrenalin bewirkt, wahrscheinlich durch Aktivierung von Lipase, im Herzen und im arbeitenden Skeletmuskel einen Abbau von gespeicherten oder im Plasma transportierten Triglyceriden.
    Notes: Summary The arteriovenous differences of total and individual free fatty acids (FFA) have been determined in the myocardium, in the electrically stimulated skeletal muscle (gastrocnemius) and in the kidney of closed chest anesthetized dogs. The concentration of total FFA was determined by titration, their composition was determined by gaschromatography. When the arterial concentration of total FFA was increased by norepinephrine infusions the percentage of olic and of palmitic acid increased and the percentage of stearic and linolic acid decreased. When the concentration of total FFA was decreased by glucose infusions the percentage of olic and palmitolic acid decreased and the percentage of palmitic and stearic acid increased. Under control conditions in the myocardium 44% of the total FFA extraction were related to olic and 24% to palmitic acid and in the skeletal muscle 43% were related to olic and 29% to palmitic acid. During norepinephrine induced increases of arterial FFA concentration myocardium and skeletal muscle extracted only olic, palmitic and palmitolic acid. At the same time in the myocardium stearic and linolic acid and in the skeletal muscle stearic acid was produced. In the kidney under control conditions 40% of the total FFA extraction were related to palmitic and 40% to olic acid. Since the extraction of olic, palmitic and palmitolic acid was higher than the extraction of other FFA at comparable arterial concentrations, it is concluded, that these three FFA are used in preference to other FFA as energy sources. Norepinephrine causes, probably via activation of lipase, in the myocardium and in the working skeletal muscle a breakdown of stored or in plasma transported triglycerides.
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    Diabetologia 3 (1967), S. 249-265 
    ISSN: 1432-0428
    Keywords: Spontaneous Diabetes ; Dog ; Cat ; Diabetes in dogs and cats ; Pancreas ; Islets of Langerhans ; B cells ; Insulitis ; Hyalin ; Capillaries ; Kidney ; Retina ; Microaneurysms ; Pituitary
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Les auteurs présentent une étude histopathologique de 30 chiens et de 5 chats spontanément diabétiques. — Les îlots de Langerhans et les cellules B étaient fortement diminués en nombre chez la grande majorité des chiens. Les cellules B étaient souvent dégranulées et hydropiques. Chez les chiens dont le diabète avait évolué pendant longtemps, les îlots étaient très rares et les cellules B absentes. — Chez les 5 chats spontanément diabétiques par contre, les îlots et les cellules B étaient nombreuses. Les cellules B étaient dégranulées et hydropiques chez 4 chats. Chez 1 des chats, les cellules B paraissaient normales. De nombreux îlots présentaient des dépôts de substance hyaline dans le stroma. Chez un chat, il existait une infiltration lymphocytaire très dense dans un îlot. — Ni chez les chiens, ni chez les chats, il n'a été vu de lésions glomérulaires identiques à celles de glomérulosclérose diabétique humaine. Les lésions les plus fréquentes consistaient en un épaississement des axes membraneux des touffes glomérulaires et une hypertrophie de la paroi des artérioles afférentes.— Dans les rétines des chiens diabétiques il existait une acellularité focale ou généralisée de la paroi des capillaires. Un petit nombre de microanévrysmes ont été trouvés chez 3 chiens diabétiques. L'incidence plus faible des lésions de rétinopathie vasculaire, comparativement aux diabétiques humains, s'explique probablement par la durée de vie plus courte du chien et du chat. Il est possible aussi que les capillaires rétiniens de ces animaux soient moins susceptibles de développer des lésions dégénératives. — Un degré marqué de stéatose hépatique a été observé chez beaucoup de chiens et de chats. Les surrénales étaient souvent hypertrophiées et contenaient des adénomes, mais ces lésions ne paraissent pas différentes de celles que l'on peut trouver chez des chiens et des chats non diabétiques de même âge. L'hypophyse a été prélevée chez 7 chiens. Dans 2 cas, elle contenait un adénome. Une étude cytologique plus complète des hypophyses sera publiée ultérieurement.
    Abstract: Zusammenfassung Die Autoren berichten über die Ergebnisse von Untersuchungen an 30 spontan-diabetischen Hunden und 5 spontan-diabetischen Katzen. Bei der großen Mehrzahl der diabetischen Hunde war die Zahl der Langerhansschen Inseln und der B-Zellen stark herabgesetzt. Die B-Zellen waren oft degranuliert und hydropisch. Bei Hunden mit schon lang anhaltender Krankheit waren die Inseln nur noch vereinzelt und B-Zellen überhaupt nicht mehr nachweisbar. — Im Gegensatz zu diesen Ergebnissen fanden sich bei allen 5 Katzen zahlreiche Inseln und B-Zellen. Bei 4 dieser Katzen jedoch waren die B-Zellen, wie bei den Hunden, degranuliert und hydropisch entartet. Bei einer Katze war das Aussehen der B-Zellen normal. Im Stroma der Inseln von 2 Katzen konnten starke Hyalinablagerungen nachgewiesen werden. In einem Falle zeigten die Inseln eine starke lymphocytäre Infiltration. — Weder bei den Hunden noch bei den Katzen waren typische Läsionen der Glomeruli, wie sie bei der Glomerulosklerose des menschlichen Diabetes auftreten, nachweisbar. Die häufigsten Veränderungen bestanden aus einer mehr oder weniger ausgeprägten Verdickung des mesangialen Teils der Kapillaren der Glomeruli und aus einer Hypertrophie der Wand der zuführenden Arteriolen. Bei einigen Hunden und Katzen bestanden auf chronische Pyelonephritis zurückführende Narben. — In der Retina der diabetischen Hunde waren zellenlose und funktionslose Kapillaren vorhanden, und degenerierte Pericyten (“ghostcells”) waren häufiger als bei normalen Hunden. In drei Hunden wurden einige Mikroaneurismen beobachtet. Daß diese für die Retinopathie des Diabetes typischen Läsionen beim Hund verhältnismäßig selten auftreten könnte mit der kürzeren Lebensdauer der Krankheit bei diesen Tieren zusammenhängen. Es ist jedoch nicht ausgeschlossen, daß die Retina von Hunden und Katzen weniger zu degenerativen Veränderungen neigt. — In der Leber vieler Hunde und Katzen wurde eine schwere Steatose beobachtet. In vier Hunden zeigte sich beginnende Lebercirrhose. In diabetischen Hunden und Katzen waren die Nebennieren oft hypertrophisch und enthielten Adenome, die allerdings auch bei nichtdiabetischen alternden Hunden beobachtet wurden. In 2 von 7 Hypophysen diabetischer Hunde fanden sich Adenome, über deren cytologische Untersuchung in einer späteren Veröffentlichung berichtet wird.
    Notes: Summary A histological study of 30 spontaneously diabetic dogs and 5 spontaneously diabetic cats is presented. — The islets of Langerhans and the B cells were strongly reduced in number in a large majority of the diabetic dogs. The B cells were often degranulated and hydropic. In cases of longer duration, the islets were scarce and B cells could no longer be found. — In contrast to the findings in diabetic dogs, all five cats showed numerous islets and B cells. However in 4 cats, the B cells showed complete degranulation and hydropic changes, as in the dogs. In one cat, the B cells had a normal appearance. Extensive hyalin deposits were found in the stroma of the islets in 2 cats. In one cat, an islet showed a dense lymphocytic infiltration. — No lesions identical to human diabetic glomerulosclerosis were found in any of the dogs or cats. The changes most frequently observed were a variable degree of thickening of the mesangial stalk of the glomerular capillaries, and an hypertrophy of the wall of the afferent arteriole. Scars resulting from chronic pyelonephritis, were found in a few dogs and cats. — Acellular, non-functional capillaries, with degeneration of pericytes (“ghost-cells”) were found in larger numbers in the retinas of the diabetic dogs than in non-diabetic control dogs. A very few microaneurysms could be found in 3 dogs. The lower incidence of the most typical lesions of diabetic retinopathy in dogs, as compared with the human diabetic, is probably related to the shorter duration of the disease in these animals. However, a lower susceptibility of the retina of dogs and cats to develop degenerative changes cannot be excluded. — A severe steatosis was observed in the liver of many dogs and cats. In 4 dogs, the liver showed early cirrhosis. In diabetic dogs and cats, the adrenal cortex often showed hypertrophy and contained adenomas; however, these changes have also been reported in non-diabetic aging dogs. An adenoma was found in 2 of the 7 pituitaries obtained from diabetic dogs; the cytological aspect of these adenomas and of the pituitaries will be reported in a later publication.
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    Diabetologia 3 (1967), S. 266-286 
    ISSN: 1432-0428
    Keywords: Spontaneous Diabetes ; Chinese hamster ; Cricetulus griseus ; Kidney ; Renal glomerulopathy ; Capillaries ; Basement membrane ; Ultrastructure ; Mesangium
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Nous avons étudié aux microscopes optique et électronique les glomérules rénaux de 11 hamsters chinois non-diabétiques, de 4 hamsters non-diabétiques mais provenant de nichées comportant des animaux diabétiques, et de 6 animaux ayant souffert d'un diabète de durée et de sévérité variables. Le vieillissement en soi est associé à une augmentation du mésangium et à une dilatation des capillaires avec léger épaississement de la membrane basale. Chez les diabétiques sévères de type juvénile, nous avons observé des altérations profondes des cellules mésangiales, avec la formation de vésicules, de corps multivésiculaires, de vacuoles et une apparence lavée du cytoplasme avec désorganisation mitochondriale. Ce n'est qu'aux stades les plus avancés qu'on observe une augmentation de la matrice mésangiale. Aux premiers stades, les membranes basales sont minces, particulièrement pour les capillaires dilatés. A des stades plus avancés, on trouve des régions épaisses et des régions minces de la membrane basale; certainement pas d'épaississement généralisé. Bien que des altérations semblables eussent été observées avec le vieillissement simple, les altérations des cellules mésangiales, la coalescence, la dilatation cystique et la fusion des anses capillaires des glomérules sont caractéristiques d'une glomérulopathie diabétique chez les animaux jeunes. Les altérations sont beaucoup plus marquées à des stades plus avancés de l'état diabétique. La diminution du nombre des anses capillaires est probablement le résultat de la coalescence des capillaires. Les cellules épithéliales sont bien préservées dans tous les glomérules et il n'y a pas de lésions nodulaires. Nous n'avons pas observé de lésions glomérulaires semblables chez les frères et soeurs des animaux diabétiques ne souffrant pas eux-mêmes d'un diabète patent. Il semblerait y avoir une analogie entre la dilatation et la coalescence des capillaires du glomérule en présence d'altérations des cellules mésangiales et la dilatation des capillaires rétiniens associée à la dégénérescence des cellules murales, ou péricytes, chez l'homme.
    Abstract: Zusammenfassung Wir haben im Licht- und im Elektronen-Mikroskop die renalen Glomeruli von 11 Kontrolltieren, von 4 nicht-diabetischen Tieren aus gleichem Wurf wie diabetische Hamster, und von 6 Tieren mit Spontan-Diabetes verschiedenen Alters, sowie mit unterschiedlicher Dauer und Schwere des Krankheitsbildes, untersucht. Zunehmendes Alter führte zur Zunahme der mesangialen Matrix mit einiger Erweiterung der Kapillaren und Verdickung der Basalmembran. Bei früh einsetzendem schweren Diabetes wurden schwere Veränderungen der Mesangialzellen beobachtet, bestehend aus Vermehrung der vesikulären Bläschen, Entstehung von multi-vesikulären Strukturen, Vacuolen, und einem verwaschenen Aussehen des Zytoplasmas, sowie mitochondrialer Desorganisation. Bei vorgerücktem Krankheitsbild bestand eine deutliche Zunahme der mesangialen Matrix. Anfänglich war die Basalmembran dünn, besonders in den erweiterten Kapillaren. Später, wies die Basalmembran sowohl verdickte wie verdünnte Stellen auf. Obwohl ähnliche Veränderungen auch mit zunehmendem Alter zu sehen waren, ließ die Beobachtung von Veränderungen der mesangialen Zellen, von zystischer Erweiterung und Verschmelzen von Kapillarschlingen beijungen Hamstern sicher auf diabetische Glomerulopathie schließen. Diese Veränderungen waren denn auch verhältnismäßig noch deutlicher und besonders charakteristisch in späteren Stadien der Krankheit. Die Fusion von Kapillaren erklärt vielleicht die Abnahme der Zahl der Kapillarschlingen. Die Ausläufer der Epithelialzellen blieben in allen Glomeruli wohl erhalten und es waren keine noduläre Läsionen zu sehen. In den von uns beobachteten Tieren waren solche Veränderungen der Glomeruli bei nicht-diabetischen Tieren nicht zu sehen. Es wird darauf hingewiesen, daß zwischen der Erweiterung und der Fusion von Kapillarschlingen, im Zusammenhang mit Veränderung der mesangialen Zellen, und der Erweiterung von Kapillaren der Netzhaut, im Zusammenhang mit Degeneration deren Perizyten beim Menschen, eine Analogie besteht.
    Notes: Summary Light and electron microscopic studies were made of the renal glomeruli of 11 control Chinese hamsters, 4 siblings of diabetic hamsters, and 6 with spontaneous diabetes of varying age of onset, duration, and severity. Aging alone was associated with an increase in mesangial matrix and some degree of capillary dilatation and thickening of the basement membrane. In severe diabetes of early-onset, there was a marked change in mesangial cells, consisting of an increase in vesicles, multivesicular bodies, vacuoles, ghost-like appearance of the cytoplasm, and mitochondrial disorganization. Only in the more advanced stages was there an increase in the mesangial matrix. Initially, the basement membrane was thin, particularly in dilated capillaries. Measurements of the basement membrane in the later stages indicated that there were both thick and thin areas; increased thickness alone was not characteristic. Although similar findings developed progressively with age, mesangial cell alterations, coalescence and cystic dilatation and fusion of capillary loops in the glomeruli of young hamsters were characteristic findings of diabetic glomerulopathy. These findings were characteristic and disproportionately marked in any later stage of the disease. Coalescence of capillaries may have explained the decrease in the number of loops. The foot processes of the epithelial cells were well-preserved in all glomeruli and nodular lesions were not seen. There was no evidence in this series that litter-mates of diabetic animals developed such glomerular lesions in the absence of overt diabetes. An analogy was suggested between the dilatation and coalescence of glomerular capillaries associated with mesangial cell changes and the dilatation of retinal capillaries associated with degeneration of the supporting mural cells in man.
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  • 94
    Electronic Resource
    Electronic Resource
    Springer
    Diabetologia 3 (1967), S. 453-459 
    ISSN: 1432-0428
    Keywords: Urine insulin ; Radioimmunoassay ; Method ; Measurement ; Clearance ; Kidney ; Control Subjects ; Insulin-treated diabetics ; Acromegaly ; Renal failure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé 1. Des détails sont donnés sur la méthode de dosage immunologique avec double anticorps pour mesurer l'insuline dans l'urine. — 2. Il a été prouvé que la méthode est spécifique et reproductible. De l'insuline humaine ajoutée à de l'urine a été retrouvée quantitativement et les différentes dilutions et concentrations ont donné les résultats escomptés. — 3. Des urines qui ont été gardées pendant 24 heures à 4°C, n'ont pas perdu d'insuline, tandis qu'on a observé une perte de 4 à 23 % après que l'urine ait été laissée pendant 24 heures à la température de la pièce. De l'urine dont le pH a été ajusté entre 7.4 et 8.4, centrifugée et mise à — 20°C n'a pas montré de perte pendant 9 mois. On a trouvé, que l'addition d'albumine à l'urine pour prévenir l'adsorption de l'insuline sur le tube n'est pas nécessaire. — 4. L'étude de la réaction du premier anticorps a démontré que la co-précipitation non spécifique de l'insuline radio-active était inférieure à 3.5 %, et que l'addition de sodium et de chlorure ne change pas la courbe standard de l'insuline. Des tubes témoins contenant de la131I-gamma-globuline de cobaye ont montré une précipitation optimale du deuxième anticorps dans toutes les expériences faites avec de l'urine. — 5. Chez des sujets normaux la clearance rénale de l'insuline était relativement constante sur une grande échelle de taux d'insuline sérique, mais elle variait avec le poids du corps. Cependant des études préliminaires ont montré que pendant la grossesse, dans l'hypertension et les maladies vasculaires périphériques, toutes caractérisées par des taux élevés d'insuline sérique, la clearance est diminuée. Par contre dans l'acromégalie la clearance est normale, alors que les taux de l'insuline sérique et urinaire étaient élevés. Dans les maladies rénales chroniques l'excrétion urinaire de l'insuline était très forte. — 6. La détermination directe de l'insuline urinaire était réalisable chez des diabétiques traités à l'insuline, à condition que la fonction rénale soit normale; on a trouvé des anticorps anti-insuline dans les urines de ces diabétiques seulement lorsqu'il existe une protéinurie.
    Abstract: Zusammenfassung 1. In der vorliegenden Arbeit wird eine Methode zum Insulinnachweis im Urin mit einer Doppel-Antikörpermethode im einzelnen angegeben.-2. Die Methode ist spezifisch und reproduzierbar. Menschliches Insulin, das dem Urin beigegeben wurde, wird quantitativ wieder gefunden. Verdünnung und Konzentrierung bewirken proportionale Änderungen des gemessenen Insulins. — 3. Urin, der über 24 Stunden bei 4°C gehalten wurde, zeigte keinen Verlust an untersuchbarem Insulin; während nach Stehen in Raumtemperatur für 24 Stunden eine Abnahme von 4–23 % beobachtet wurde. Urinproben mit eingestelltem pH von 7.4–8.4, zentrifugiert und bei −20°C gehalten, zeigten bis zu 9 Monaten keinen Verlust. Zusatz von Albumin in den Urin, um die Adsorption von Insulin an der Glaswand zu verhüten, ist für unnötig befunden worden. — 4. Versuche der ersten Antikörper-Reaktion zeigten, daß die unspezifische Mit-Präzipitation von radioaktivem Insulin kleiner als 3.5 % war und daß die Zugabe von Natrium und Chlorid die Insulin-Standardkurve nicht verändern. Kontroll-Reagenzgläser mit131I-Meerschweinchen Gammaglobulin zeigten einen optimalen zweiten Antikörper Niederschlag in allen Urin versuchen. — 5. Die Nieren-Clearance von Insulin war bei normalen Personen über eine weite Reihe von Serum-Insulin-Werten relativ konstant, aber variierte mit der Körpergröße. Jedoch haben vorausgehende Studien darauf hingedeutet, daß die Clearance reduziert ist während der Schwangerschaft, bei hohem Blutdruck und peripheren vasculären Krankheiten, welche alle charakterisiert sind durch hohe Insulinwerte. Dafür war die Clearance bei Akromegalie normal, denn beide, Serum- und Urin-Insulinwerte waren erhöht. Bei chronischen Nierenkrankheiten war die Insulinausscheidung im Urin sehr hoch. — 6. Direkte Messung von Urin-Insulin war bei Diabetikern ausführbar die mit Insulin behandelt wurden, vorausgesehen, daß die Nierenfunktion normal war; insulin-bindende Antikörper wurden nur im Urin von Diabetikern mit Protéinurie gefunden.
    Notes: Summary 1.Details are given of a double antibody immunoassay method suitable for measuring insulin in urine. — 2. The method proved specific and reproducible. Human insulin added to urine was quantitatively recovered and dilution and concentration resulted in proportional changes in measured insulin. — 3.Urines kept at 4°C for 24 hours showed no loss of assayable insulin, while decreases of 4–23 % were observed after standing at room temperature for 24 hours; samples of urine adjusted to pH 7.4–8.4 and centrifuged were kept at −20°C for 9 months without loss. Addition of albumin to urine to prevent adsorption of insulin on the container was found to be unnecessary. — 4. Tests of the first antibody reaction showed that non-specific co-precipitation of radioactive insulin was less than 3.5 % and that addition of sodium chloride did not alter the standard insulin curve. Monitor tubes containing131I-guinea-pig gamma-globulin showed optimal second antibody precipitation in all the urine assays surveyed. — 5. In normal subjects, the renal clearance of insulin was relatively constant over a wide range of serum insulin levels, but varied with body size. However, preliminary studies suggested that the clearance was reduced in pregnancy, hypertension and peripheral vascular disease, all of which are characterized by high serum insulin values. In contrast, the clearance in acromegaly was normal as both serum and urine insulin levels were raised. In chronic renal disease the urinary excretion of insulin was very high. — 6. Direct measurement of urinary insulin was feasible in insulin-treated diabetics provided that renal function was normal; insulin-binding antibodies were found in the urine of these diabetics only in association with proteinuria.
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