Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Binding of [3H]ouabain to endothelial cells derived from various vascular beds (1987)
    Springer
    Basic research in cardiology 82 (1987), S. 544-550 
    Details
    ISSN: 1435-1803
    Keywords: endothelial cells ; [3H]ouabain binding ; ouabain receptors ; Na+/K+-ATPase ; vascular beds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Binding experiments were performed with [3H]ouabain on plasma membranes derived from several types of isolated and cultivated endothelial cells. Identical saturation curves for [3H]ouabain binding to endothelial cells form pig aorta, caval vein, and pulmonary artery were obtained with a dissociation constant (KD) of 3.29±0.31 nmol/l and a binding capacity (Bmax) of 5.22±0.12 pmol/mg protein. On guinea-pig coronary endothelial cells, saturation of [3H]ouabain revealed much lower affinity (KD 95±15 nmol/l, Bmax 2.08±0.09 pmol/mg protein). All Scatchard plots were linear, indicating a homogeneous class of binding sites. In competition experiments, cardiac glycosides and their aglycons displaced the radioligand with a structure-activity relationship typical for interaction with Na+/K+-ATPase (proscillaridin A〉ouabain〉digoxin〉g-strophanthidin〉digoxigenin〉dihydrodigoxin); in particular, removal of the sugar moiety results in considerable reduction of affinity. Furthermore, K+ displayed a steep inhibition curve with a half-maximal inhibitory constant of 2 mmol/l. All these findings suggest the presence of endothelial ouabain receptors linked to Na+/K+-ATPase. However, direct measurement of this enzyme was not possible due to an extremely high Mg2+-ATPase activity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01907224
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Cardiac ventricular β2-adrenoceptors in guinea-pigs and rats are localized on the coronary endothelium (1986)
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 334 (1986), S. 56-62 
    Details
    ISSN: 1432-1912
    Keywords: β-Adrenoceptor antagonists ; β-Adrenoceptor subtypes ; Cardiac sarcolemma ; Cardiomyocytes ; Coronary endothelial cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In mammalian heart tissue β2 are known to coexist with β1. In the present study, evidence that β2 in guinea-pig and rat ventricles are primarily localized on the coronary endothelium is provided by competition binding studies with the subtype-selective β-adrenoceptor antagonists ICI 89.406 (β1) and ICI 118.551 (β2) on four different plasma membrane preparations. (1) Following density gradient centrifugation of cardiac ventricular microsomes from rats or guinea-pigs, endothelial plasma membranes migrated at slightly higher density than the sarcolemmal membranes, as verified by endothelial (angiotensin converting enzyme) and sarcolemmal markers (adenylate cyclase, [3H] ouabain binding). At the activity peak of angiotensin converting enzyme, the relative amount of β2 in guinea-pigs and rats was 25% and 65%, respectively. (2) On sarcolemmal membranes corresponding to the activity peak of adenylate, cyclase, β-adrenoceptors consisted of the β1 exclusively (guinea-pig), or to at least 90% (rat). (3) Cultures of coronary endothelial cells derived from guinea-pigs revealed only β2. (4) Isolated guinea-pig cardiomyocytes contained only β1, a finding recently established in rat myocytes as well.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00498740
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Estimation of glomerular filtration rate in anorectic adolescents (1989)
    Springer
    Pediatric nephrology 3 (1989), S. 16-21 
    Details
    ISSN: 1432-198X
    Keywords: Kidney function ; Glomerular filtration rate ; Creatinine ; Malnutrition ; Muscle mass ; Anthropometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Severe malnutrition has been associated with a decrease in fat and lean body mass, as well as in renal function. This study was designed to evaluate the estimation of glomerular filtration rate (GFR, ml/min per 1.73 m2) in malnourished teenagers, by using the formula GFR=kL/P cr (whereL is body height,P cr is plasma creatinine concentration and k is a proportionality constant relating muscle mass to body size that has been found to equal 0.7 in adolescent boys and 0.55 in girls). Body composition was estimated using anthropometric measurements and urinary creatinine excretion (UcrV). Malnourished female patients showed depletion of fat and muscle, whereas males had primarily decreased muscle mass. There was a good correlation (r=0.74) between anthropometric [arm muscle volume (AMV)] and chemical UcrV estimates of muscle mass. However, our previously validated estimate of GFR did not give reliable results in this group of malnourished teenagers, probably because their muscle mass was so greatly altered by the severity of malnutrition. Therefore, we used anthropometric measurements and Pcr, to estimate GFR by multiple linear regression. The best prediction was obtained by using AMV/Pcr and the observed/expected (for age, height and sex) weight ratio (WR): $$\begin{gathered} GFR (ml/min) = 0.06 AMV/P_{{\text{cr}}} + 131{\text{ WR - 79,}} \hfill \\ r = 0.82,n = 13. \hfill \\ \end{gathered} $$ We confirm that malnutrition in adolescents is associated with decreased GFR and conclude that the resulting variability in body composition limits the possibility of estimating GFR from Pcr and height. A somewhat better estimate may be obtained from simple anthropometric measurements and Pcr.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00859618
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    306. ATP-MgCl2 und Adenosin (AD) im akuten Nierenversagen: Experimentelle Ansätze zu einem kausalen Behandlungsprinzip (1985)
    Springer
    Langenbeck's archives of surgery 366 (1985), S. 709-710 
    Details
    ISSN: 1435-2451
    Keywords: Renal ischemia ; ATP-MgCl2 ; Adenosine ; Nierenischämie ; ATP-MgCl2 ; Adenosin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die intraaortale Gabe von ATP-MgCl2 and AD nach 70–90 min Nierenischämie verbesserte bei Hunden die Struktur and Funktion der Nieren and damit die Überlebensrate. Zur Klärung der Wirkungsmechanismen exogener Purine wurde Hunden intraaortal 14C-ATP oder 14C-AD nach 70 min Nierenischamie verabreicht. Mittels Hochdruckflüssigkeitschromatographie konnten im Nierengewebe radioaktives AMP, ADP and ATP, im Nierenvenenblut radioaktives AD und seine Abbauprodukte, vor allem Harnsäure gemessen werden. SchluBfolgerung: Unabhängig davon, ob ATP oder AD infundiert werden, kommt es in postischämischen Tubuluszellen zu einer ATPSynthese aus präformierten Purinkörpern. Möglicherweise beruht der protektive Effekt deshalb auf einer Verbesserung der Energiebilanz.
    Notes: Summary In dogs, intra-aortal infusion of ATP-MgCl2 and AD after 70–90 min renal ischemia improved kidney morphology and function and thus the survival rate. In order to evaluate the mode of action of exogenous purine, dogs received C14-ATP or C14-AD following 70-min renal ischemia. HPLC revealed radioactive AMP, ADP and ATP in the kidney and radioactive AD and degradatives, mainly uric acid, in the renal vein.Conclusion: Regardless of whether ATP or AD are infused postischemically or not, tubular cells can utilize preformed purines for restoration of adenine nucleotide pools. It is postulated that the protective effect of postischemically applied purines is due to an improvement in the energy charge in the kidney.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01836904
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    A new selective medium for the isolation ofCampylobacter jejuni from human faeces (1983)
    Springer
    European journal of clinical microbiology & infectious diseases 2 (1983), S. 389-393 
    Details
    ISSN: 1435-4373
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A new selective medium, Butzler's medium Virion, for the isolation ofCampylobacter jejuni from human faeces is described. This medium contains the following antibiotics per liter: cefoperazone 15 mg, rifampicin 10 mg, colistin 10,000 IU, and amphotericin B 2 mg. At 42 °C there was no difference in the isolation rate on Butzler's medium Virion and Butzler's medium Oxoid, but the competing faecal flora was best suppressed by the new medium which allows easier reading of plates and better recognition of campylobacter colonies. Also, the isolation rate and growth of faecal flora were comparable when this new selective medium was incubated at both 37 °C and 42 °C in a candle jar or a special incubator. These results suggest that Butzler's medium Virion is a very reliable medium for the isolation of campylobacter. In comparison with other selective media it has important advantages for investigators who have little experience in isolating this enteropathogen, or for developing countries where special 42 °C incubators are often not available.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02019476
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    303. Untersuchungen zur Antithrombogenität der Venenwand (1985)
    Springer
    Langenbeck's archives of surgery 366 (1985), S. 708-708 
    Details
    ISSN: 1435-2451
    Keywords: Endothelial layer ; Ecto-ADPase ; Adenosine ; Reendothelialization ; Venöses Endothel ; Ekto-ADPase ; Adenosin ; Reendothelialisierung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Das Endothel eines isoliert perfundierten Venensegmentes (V. cava inferior des Hasen) baut intravasal appliziertes 5′ Adenosindiphosphat (ADP) schnell zu antithrombogenen Adenosin ab (2,3±0,2 nmol/minx 106 Zellen). Der ADP-Abbau durch Blutzellen ist vergleichsweise langsam (0,0007 ± 0,0002 nmol/min x 106 Zellen). Nach Schädigung des Endothels mit dem FogartyKatheter kann die verbleibende GefdBwand ADP zwar nahezu ebenso rasch abbauen, Plättchen inhibierendes Adenosin entsteht jedoch in geringeren Mengen. Dieser Befund normalisiert sich nach Reendothelialisierung.
    Notes: Summary In the isolated perfused vena cava inferior of the rabbit, platelet-aggregating ADP is rapidly degraded to platelet-inhibiting adenosine (2.3±0.2 nmol/minx 106 cells). In contrast ADP degradation by blood cells is relatively slow (0.0007 ± 0.0002 nmol/min x 106 cells). After damage of the endothelial layer by a Fogarty catheter, the ADP degradation activity of the vessel wall does not change; adenosine, however, acumulates in lower quantities. Reendothelialization of the vessel wall causes physiological adenosine production from ADP degradation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01836901
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    The coronary endothelium: a highly active metabolic barrier for adenosine (1985)
    Springer
    Basic research in cardiology 80 (1985), S. 515-529 
    Details
    ISSN: 1435-1803
    Keywords: adenosine ; coronary flow ; coronary endothelium ; A2-receptors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cultured coronary endothelial cells and the coronary endothelium of isolated perfused guinea-pig hearts are characterized by a very active adenosine and adenine nucleotide metabolism. Adenosine applied to the endothelium at low concentrations is avidly metabolized and preferentially incorporated into different nucleotide pools—only a minor amount is degraded to uric acid. Physiologically, the coronary endothelium therefore functions as an impermeable metabolic barrier for interstitially or intravascularly accumulating adenosine. Only at concentrations≧10−6M adenosine can pass the endothelial barrier. As a consequence, the vasodilatory action of adenosine formed in or administered into the coronary system cannot be induced by a direct association of the nucleoside with the putative adenosine receptor of the arteriolar smooth muscle cells, but must be mediated by the endothelium. High molecular weight derivatives of adenosine, clearly confined to the coronary system, can also induce a coronary dilation. The endothelium-mediated smooth muscle relaxation is therefore obviously due to triggering of an extracellular adenosine receptor at the luminal surface of the endothelium. Since this process is accompanied by a rapid and pronounced activation of the adenylate cyclase system, the endothelial receptor conforms to an A2-type. According to our results it is necessary to reconsider qualitative and quantitative facets of the adenosine hypothesis of metabolic regulation of coronary blood flow, which—in its original formulation —exclusively centers on the cardiomyocyte metabolism. With respect to the vasoactivity of adenosine one obviously has to distinguish between its action from the interstitial space directly via the myocyte receptors of the vessel wall, and/or its action from the intracoronary space via the newly detected endothelial A2-receptor. More information is needed to determine the extent to which both receptor populations actually participate in the metabolic regulation of coronary flow under physiological and pathophysiological conditions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01907915
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Eine neuartige Zellkulturanlage für die Massenproduktion tierischer Zellen im Suspensionsverfahren (1984)
    Springer
    Fresenius' Zeitschrift für analytische Chemie 317 (1984), S. 742-743 
    Details
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00593895
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...