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  • 1970-1974  (443)
  • 1965-1969  (63)
  • 1850-1859
  • Rat  (319)
  • Electron Microscopy
  • 1
    ISSN: 1434-4726
    Keywords: Spiral ganglion and Organ of Corti ; Electron Microscopy ; Influence of Different Fixatives and Fixation Methods
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Das Ganglion spirale und Cortische Organ des Meerschweinchens wurden nach Osmium- und kombinierter Glutaraldehyd-Osmiumfixation sowie Anwendung verschiedener Fixationsmethoden elektronenmikroskopisch untersucht. Die Strukturen des Cortischen Organs wurden hierbei nicht wesentlich beeinflußt. Am Ganglion spirale ergaben sich Unterschiede im Aufbau der Myelinhüllen der Ganglienzellen. Es wird diskutiert, daß es sich beim semikompakten Myelin um ein Artefakt der Osmiumfixation handelt und daß Glutaraldehyd den Aufbau der Myelinhüllen im Bereich der Spiralganglienzellen naturgetreuer wiedergibt als Osmium.
    Notes: Summary We have been examining with the electron microscope the spiral ganglion and the organ of corti in guinea pigs, using osmium and a combined glutaraldehyde-osmiumfixation together with various fixation techniques. The structures of the organ of corti were not considerably effected. Differences in the structure of the myelin sheets of ganglion cells were found in the spiral ganglion. Presumably the semicompact myelin represents an artefakt after osmium-fixation, glutaraldehyde being able to demonstrate clearer the structure of the myelin sheets on spiral ganglion cells compared to osmium.
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 281 (1974), S. 197-217 
    ISSN: 1432-1912
    Keywords: Intestinal Absorption ; Acidic Drugs ; Benzoic Acid ; Salicylic Acid ; Solvent Drag ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Jejunal loops of anaesthetized rats were perfused with hypotonic, isotonic and hypertonic buffered solutions containing 14C-labelled benzoic acid and salicylic acid at pH 6.2 and 2.2. The blood flow of the loop was maintained at an intermediate rate (0.78–0.97 ml min−1 g−1). The water net flux was determined by polyethylene glycol as non-absorbable marker and amounted up to +31 or-27 μl min−1 g−1. 2. A positive water net flux (leaving the gut lumen) increased the appearance rate of benzoic acid and salicylic acid in the intestinal venous blood by maximally 47 and 41%, a negative water net flux (entering the gut lumen) diminished the appearance rate by 28 and 37%. 3. The experimental data were analysed by means of a kinetic model. The parameters of the model were the epithelial permeability kF D , the serosal permeability k S F S and the sieving coefficient Φ=1−σ. The epithelial permeability was 0.115 and 0.107 for benzoic acid and salicylic acid at pH 6.2 and increased to 0.163 and 0.185 ml min−1 g−1 at pH 2.2. The serosal permeability was assumed to be identical for neutral and acidic pH and amounted to 0.046 and 0.112 ml min−1 g−1 indicating that a certain proportion of the absorbed drugs was transferred to the serosal side. The sieving coefficient was 2.92 and 2.31 at neutral pH and 3.79 and 3.56 at acidic pH. 4. The main resistance to the absorption of the two drugs is the epithelial membrane, since the effective blood flow and the unstirred layer are not ratelimiting. The high sieving coefficient for the two drugs is interpreted as indicating an interaction of drug and water molecules inside the lipid part of the cell membrane (which contains at least 30% water). The electric potential across the gut wall may contribute to the size of the sieving coefficient, if the drug molecules permeate also in the ionized form. 5. Using acidic perfusion solutions the epithelial permeability and the sieving coefficient were increased by the factor 1.3–1.5. This increase can be explained sufficiently by a facilitated entrance of the unionized drug molecules into the epithelial membrane.
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 16 (1974), S. 109-127 
    ISSN: 1432-0827
    Keywords: Dentinogenesis ; Diphosphonates ; Calcification ; Collagen ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract The effects of high doses of ethylene-1-hydroxy-1,1-diphosphonate (EHDP) were investigated at the light microscopic and subcellular level. The administration of EHDP at a concentration of 7.5–10 mg P/kg body weight/day over a short period of time resulted in complete inhibition of crystal formation in predentin and pre-enamel. An increased predentin width was observed and within newly-formed predentin areas the formation ofcollagen fibrils was grossly disturbed. In addition, fine precipitates appeared in the ground substance. The presence of unusual thread-like elements within specific bodies in the cytoplasm of the odontoblastic processes may be indicative of an interference by EHDP in e.g. the synthesis of precollagen. The possibility of an inhibition by EHDP of the extracellular aggregation of collagen molecules is also discussed. EHDP further inhibited crystal formation within dentinal globules. Functioning ameloblasts were grossly affected in EHDP-treated rats, and it is suggested that this is related to an inhibition of crystal formation in pre-enamel.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 364 (1974), S. 111-127 
    ISSN: 1432-2307
    Keywords: Electron Microscopy ; Coronary Arteries ; Atherosclerosis ; Aging ; Smooth Muscle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The coronary arteries were studied by electron microscopy in normal rats weighing 65 to 535 gm; fixation was accomplished by perfusion for 20 min at 110–130 mm Hg. In rats of all ages (but especially in the oldest) the arterial wall contained deposits of abnormal intercellular material, consisting of granules, vesicles, myelin figures and other debris. These deposits were present in the intima and media, but rare in the adventitia; there was suggestive evidence that medial cells phagocytized some of the material. The adventitia was characterized by 1–4 layers of cells with extremely thin protoplasmic expansions wrapped around the vessel (“veil cells”) and containing lysosome-like bodies as well as phagosomes. These findings, taken as a whole, suggest the following sequence of events. During normal life, the media produces cellular debris, by cell death as well as by fragmentation of cellular processes; part of these debris are phagocytized by smooth muscle cells, part diffuse outward to the adventitia where they are taken up by specialized cells (the “veil cells”). However, due to relative inadequacy of phagocytosis in the media, the debris continue to accumulate and form intercellular deposits that increase with age. It is possible that this natural phenomenon may by itself set a maximal limit to the life-span of the arterial wall.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Virchows Archiv 363 (1974), S. 249-258 
    ISSN: 1432-2307
    Keywords: Hypertensin (Angiotensin) ; Catecholamins ; So-Called Epinephrine Myocarditis ; Rat Heart ; Optical Microscopy ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Pathomorpliological comparative studies on structural damage to rat cardiac muscle following administration of hypertensin and arterenol, with and without pretreatment with reserpine to empty the catecholamine reserves were performed. The question is whether and to what degree angiotensin induced cardiac damage, which is viewed microscopically as the so-called epinephrine myocarditis, can be regarded as an indirect catecholamine effect. The following could be deduced: 1. Hypertensin causes a damage pattern similar to that of arterenol as seen under the light microscope and corresponds to the so-called epinephrine myocarditis. 2. The electron microscope demonstrates definite differences in the pattern of damage to the myocardium: hypertensin affects primarily the mitochondria, while arterenol affects the myofibrils. 3. Hypertensin and arterenol damage mainly the subendocardial tissue of the left heart: hypertensin affects more the region of the base of the left ventricle, arterenol more the region of the left ventricle apex. 4. Pretreatment with reserpine blocks the damaging effects of hypertensin in the rat heart for 12 hours. After 24 hours the full picture of the damage pattern has reappeared. Arterenol is lethal to animals pretreated with reserpine. 5. The pathogenesis of the damaging effects of hypertensin on rat cardiac muscle is discussed.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Research in experimental medicine 162 (1974), S. 63-66 
    ISSN: 1433-8580
    Keywords: Rhyolithic pumice ; Ferrihexacyanoferrate (II) ; Thallium ; Rat ; Rhyolithischer Bims ; Ferrihexacyanoferrat (II) ; Thallium ; Ratte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Orale Verabfolgung von rhyolithischem Bims bewirkt eine herabgesetzte Retention von Thallium in den Geweben. Die Wirksamkeit von Rhyolith zeigt eine ausgeprägte Dosisabhängigkeit, ist aber geringer als die von Ferrihexacyanoferrat (II).
    Notes: Summary Oral administration of rhyolith leads to a diminished retention of thallium by the tissues. The effectiveness of rhyolith markedly depends on its dosage, but is surpassed by that of ferrihexacyanoferrate (II).
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Research in experimental medicine 163 (1974), S. 39-45 
    ISSN: 1433-8580
    Keywords: D-penicillamine ; Acetazolamide ; Renal excretion ; Rat ; D-Penicillamin ; Acetazolamid ; Renale Exkretion ; Ratte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die renale Ausscheidung von D-Penicillamin läßt sich weder durch Probenecid noch durch N-Methylnicotinamid oder NH4Cl beeinflussen. Acetazolamid bewirkt eine erhöhte Retention von D-Penicillamin in Haut und Muskulatur und hemmt dessen renale Ausscheidung, hat jedoch keinen Effekt auf die Dekorporationswirksamkeit von D-Penicillamin bei60Co. Die möglichen Ursachen des Einflusses von Acetazolamid auf die Verteilung und Exkretion von D-Penicillamin werden diskutiert.
    Notes: Summary The renal excretion of D-penicillamine is not influenced by probenecid, N-methylnicotinamide, and NH4Cl. Acetazolamide brings about an increased retention of D-penicillamine in skin and muscles and lowers its urinary excretion, but does not exhibit any influence on the efficacy of D-penicillamine in removing internally deposited60Co. The possible causes for the action of acetazolamide on the distribution and excretion of D-penicillamine are discussed.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Research in experimental medicine 163 (1974), S. 341-349 
    ISSN: 1433-8580
    Keywords: Experimental uremic syndrome ; Rat ; 5/6 reduction of renal parenchyma ; Serum- and urine analysis ; Secondary hyperparathyroidism ; Experimentelles urämisches Syndrom ; Ratte ; 5/6-Reduktion des Nierenparenchyms ; Serum- und Urinanalyse ; Sekundärer Hyperparathyreoidismus
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Durch eine 5/6-Nierenparenchymreduktion wurde an Ratten ein chronisches, durch bilaterale Nephrektomie ein akutes urämisches Syndrom erzeugt. Beim chronischen urämischen Syndrom erwiesen sich in der Serumanalyse die Konzentrationen des Harnstoffstickstoffs und des Kreatinins als wesentlich erhöht. Darüber hinaus bestanden alle chemischen Zeichen eines sekundären Hyperparathyreoidismus. Die Tiere litten außerdem an einer schweren Poly-, Protein- und Albuminurie. Überraschenderweise war aber der Spiegel des totalen Serumproteins gegenüber den Kontrolltieren erhöht. Das experimentelle chronische urämische Syndrom stellt eine extreme Adaptation der regulatorischen Aktivität des Nierenrestparenchyms und des ganzen Organismus dar. Beim akuten, durch bilaterale Nephrektomie erzeugten urämischen Syndrom besteht dagegen ein schweres Versagen der Regulation des Wasser- und Elektrolytstoffwechsels, welches innert 50–60 Std zum Tode der Versuchstiere führt.
    Notes: Summary A chronic uremic syndrome was induced by 5/6 nephrectomy and an acute uremic syndrome by bilateral nephrectomy in rats. In the chronic uremic syndrome serum and urine analysis revealed a highly increased serum level of BUN and creatinine. Furthermore, all chemical signs typical of secondary hyperparathyroidism were present. The animals suffered from severe polyuria, protein- and albuminuria but, surprisingly, the total serum protein was increased. The experimental chronic uremic syndrome is, in essence, a syndrome of “extreme adaptation” of the regulatory activity of remnant renal parenchyma and of the whole body. In contrast, the acute uremic syndrome induced by bilateral nephrectomy is a severe disorder of water and electrolyte metabolism resulting in death of the experimental animals after 50–60 hrs.
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  • 9
    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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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Research in experimental medicine 162 (1974), S. 313-321 
    ISSN: 1433-8580
    Keywords: Coprophagy ; Rat ; Calcium metabolism ; Bone morphology ; Immobilization ; Koprophagie ; Ratte ; Calciumstoffwechsel ; Knochenmorphologie ; Immobilisierung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Wir untersuchten den Einfluß der Koprophagie auf den Calciumstoffwechsel der Ratte. 20 Versuchstiere wurden durch Einschnüren in einen Lederpanzer an der Koprophagie gehindert und mit 21 Kontrolltieren gleicher Futteraufnahme verglichen. Die Kinetik des Calciumstoffwechsels wurde unter Verwendung von45Ca als Tracer analysiert. Die radiochemischen Resultate wurden mit den histologischen Beobachtungen an den Epi-Metaphysen der Kniegelenke verglichen. Bei den Versuchstieren mit verhinderter Koprophagie fanden wir: 1. ein hochsignifikant niedrigeres Körpergewicht; 2. eine hochsignifikante Verkleinerung folgender Parameter des Calciumstoffwechsels: Compartmentgröße und Austauschrate zwischen ihnen, Calciumausscheidungsraten, Knochenan- und -abbau; 3. eine Verschmälerung der Wachstumsfuge, verkürzte und verschmälerte primäre Knochenbälkchen, verminderte sekundäre metaphysäre Spongiosa. Bei 4 Versuchstieren, die in Lederpanzern gehalten, denen jedoch die Koprophagie ermöglicht war, wurden gleichartige histologische Veränderungen wie bei verhinderter Koprophagie festgestellt. Es wird gefolgert, daß die Verhinderung der Koprophagie keinen meßbaren Einfluß auf die Parameter des Calciumstoffwechsels hat.
    Notes: Summary We investigated the influence of coprophagy on the calcium metabolism of the rat. 20 experimental animals were prevented from coprophagy by wrapping them in leather harnesses and compared with 21 controls on the same food intake. Kinetics of calcium metabolism were analysed using45Ca as tracer. The radiochemical results were compared with the histological observations in the epi-metaphyses of the knee joints. In the experimental animals prevented from coprophagy we found: 1. a highly significant lower body weight; 2. a highly significant diminution of the following parameters of calcium metabolism: compartment sizes and exchange rate between them, calcium excretion rates, bone accretion and resorption; 3. a narrower epiphyseal growth cartilage, clearly shorter and narrower primary trabeculae, rarefied secondary metaphyseal trabeculae. Histological alterations identical to those observed with coprophagy prevented, were found in 4 animals kept in harnesses but with coprophagy allowed. It is concluded that prevention of coprophagy has no measurable influence on the parameters of calcium metabolism.
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Research in experimental medicine 163 (1974), S. 289-298 
    ISSN: 1433-8580
    Keywords: Gastrinpentapeptide ; Vagotomy ; Acid secretion ; Perfusion test ; Rat ; Gastrinpentapeptid ; Vagotomie ; Säuresekretion ; Perfusionsversuch ; Ratte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Bei männlichen Wistarratten wurde eine trunkuläre beiderseitige Vagotomie — ergänzt durch eine Pyloroplastik — angelegt. 4 Wochen später erfolgte in Urethannarkose eine Perfusion des Magens mit 0,9%iger NaCl-Lösung in Anlehnung an die Versuchsanordnung von Ghosh. Die Vollständigkeit der Vagotomie bestätigte ein Hypoglykämietest. Im Abstand von 150 min erhielten die Tiere — in 6 Gruppen zu je 10 Ratten — 2 × 50, 100, 150, 200, 250 oder 300 µg/kg KG Pentagastrin subcutan. Die statistisch ausgewerteten Ergebnisse lassen sich wie folgt zusammenfassen: 1. Die nach dem Abklingen der Wirkung der ersten Pentagastrininjektion wiederholte Pentagastringabe in derselben Dosis ergab bei allen Dosierungen eine höhere Säuresekretion als nach der ersten Injektion. 2. Ein Maximum der sezernierten Säuremenge wurde bei einer Dosis von 100 µg/kg KG erreicht. Bei höherer Dosierung des Pentagastrins nahm die Menge der sezernierten Säure signifikant ab.
    Notes: Summary Male Wistar rats were subjected to a complete bilateral vagotomy and a pyloroplasty. 4 weeks later followed in urethane anesthesia a continuous perfusion of the stomach with 0.9% saline according to the rat preparation of Ghosh. The completeness of the gastric vagotomy was confirmed by a postoperative insulin test. In an interval of 150 min the rats — in 6 groups of 10 rats each — were two times injected pentagastrin subcutaneously in dose rates of 50, 100, 150, 250 or 300 µg/kg body weight. The statistical confirmed results can be summarized as followed: 1. The second injection of pentagastrin — 150 min after the first — in the same dose produced a significantly higher gastric acid secretion in the rat all dose rates in comparison to the first injection. 2. The maximal gastric acid secretion was produced by a dose rate of 100 µg/kg body weight of pentagastrin. At higher dose rates of pentagastrin there was a significant reduction of gastric acid secretion.
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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 143 (1974), S. 255-262 
    ISSN: 1432-0568
    Keywords: Median eminence ; Neuro-vascular contacts ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The vascular surface of the external layer of the median eminence is composed of neuronal and glial processes. Neuro-vascular contacts are supposed to be necessary for the release of hypophysiotropic neurohormones. The present study confirms the hypothesis that the relative extent of neuro-vascular and glio-vascular contacts varies under different functional conditions of the tubero-hypophysial system. Morphometric analysis shows that in normal rats about 20% of the surface is lined by neuro-vascular contacts. After bilateral adrenalectomy the neuro-vascular contacts are enlarged to 40% whereas application of an extract of stalk-median eminence tissue is followed by a decrease of the neuro-vascular contacts to 15%. The implications of these results are discussed.
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  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 143 (1974), S. 185-203 
    ISSN: 1432-0568
    Keywords: Basement membrane labyrinths ; Cerebral ventricles ; Development ; Rat ; Light and Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Gehirne embryonaler und neugeborener Ratten wurden im Hinblick auf die frühe Entstehung der Basalmembranlabyrinthe licht- und elektronenmikroskopisch untersucht. 1. An den Hirngefäßen embryonaler Ratten der 2. und 3. Fetalwoche kommen zwar bereits Basalmembranen vor, sub- oder interependymale Basalmembranlabyrinthe fehlen aber noch. 2. Basalmembranlabyrinthe werden mit der Perjodsäure-Bisulfit-Aldehydthionin-Methode lichtmikroskopisch ab dem 20. Tag an umschriebenen Stellen des Ventrikelsystems gefunden; elektronenmikroskopisch treten die ersten Basalmembranlabyrinthe am 12. postnatalen Tag auf. 3. Die ersten interependymalen Labyrinthe erscheinen in Erweiterung der interependymalen Spalten in der Nähe von ausgedehnten Golgifeldern. Der Labyrinthinhalt besteht aus einer feinflockigen Substanz. Diese liegt wolkenartig angehäuft gegenüber bogenförmigen Ausbuchtungen lokal verbreiterter Zellmembranen. In Ausbildung begriffene Labyrinthe zeigen eine lamelläre Gliederung. 4. Ab dem 12. postnatalen Tag treten auch an den Basalmembranen der pericapillären Zellen, in denen lichtmikroskopisch Glykoproteide nachweisbar sind, zapfenartige Duplikaturen auf. Die Zapfen sind überwiegend ependymwärts gerichtet. Verbindungen zwischen den Basalmembranzapfen und den interependymalen Basalmembranlabyrinthen werden in den ersten 30 Lebenstagen nicht gefunden. 5. Sowohl an den die interependymalen Labyrinthe begrenzenden Plasmalemmata als auch am Plasmalemm der pericapillären Zellen fallen Stachelsaumbläschen auf, deren Membran in die Zellwand eingebaut wird. Ihr Inhalt scheint in die entstehenden Labyrinthe entleert zu werden. 6. Da sich an den tubulären Enden der Doppellamellen der Dictyosomen Strukturen befinden, die den Stachelsaumbläschen morphologisch gleichen, und da im Bereich des Golgifeldes und im Cytoplasma zwischen diesem und der Zellwand zahlreiche Stachelsaumbläschen liegen, wird angenommen, daß das Material der Basalmembranlabyrinthe dem Golgiapparat entstammt und vermittels der Stachelsaumbläschen zur Zellwand transportiert wird. Bogenförmige Ausbuchtungen lokal verbreiterter Zellmembranen im Bereich entstehender Labyrinthe werden als Reste von Stachelsaumbläschen aufgefaßt, deren Membran in die Zellwand eingebaut wurde. 7. Da die phylogenetische Zunahme des Hirnmantels mit einem Verlust der langen in das Gehirn reichenden basalen Ependymfortsätze an den größten Teilen der Ventrikelwand einhergeht und niedere Tiere noch nicht über Basalmenbranlabyrinthe verfügen, wird angenommen, daß diese die Transportfunktion für Stoffe aus dem Liquor übernommen haben, die vordem nach allgemeiner Auffassung über die langen Fortsätze in das Gehirn gelangten.
    Notes: Summary The brains of embryonic and new-born rats were investigated by means of light- and electron microscopy with regard to the early formation of basement membrane labyrinths. 1. Though basement membranes are already found around the brain capillaries of embryonic rats from the 2nd week of pregnancy, sub- and interependymal basement membrane labyrinths are still absent. 2. Basement membrane labyrinths, being demonstrable for light microscopy by a periodicacid-bisulfite-aldehydethionin-method, appear around the 20th day after birth at certain places of the ventricular system. By means of electron microscopy, basement membrane labyrinths have first been detected at the 12th postnatal day. 3. The earliest interependymal basement membrane labyrinths are found in enlargements of the interependymal spaces near a distended Golgi apparatus. The contents of the labyrinths, being composed of a loose flocculent material, are of a lamellar structure. In the intercellular space the material is situated opposite bow-shaped excavations of local broadenings of cell membranes. 4. From the 12th postnatal day, plug-like duplications of basement membranes occur at the ependymal side of the pericapillar cells, which contain glycoproteids. The plugs of basement membranes are directed towards the ependymal layer. No connections between the interependymal basement membrane labyrinths and the plugs of pericapillary basement membranes exist within the first 30 days of life. 5. At the plasmalemma of ependymal cells bordering the interependymal labyrinths, and at the cell membrane of pericapillary cells, coated vesicles are to be found, which are fused with the cell membrane. The contents of these vesicles seem to be released into the developing labyrinths. 6. At the tubular ends of dictyosomes, coated vesicle-like structures can be demonstrated. In the environment of the Golgi apparatus many coated vesicles are situated; they can even be found between the Golgi apparatus and the walls of labyrinthś. Therefore the coated vesicles are considered to be transport vesicles, transporting the material which is formed in the Golgi apparatus towards the cell membrane. 7. Since the phylogenetic increase of the brain mantle is accompanied by loss of the long processes of ependymal cells that reach far into the brain, and since lower animals have no basement membrane labyrinths, it is suggested that the basement membrane labyrinths have a transport functions for material from the cerebrospinal fluid which in lower animals is assumed to be transported by the long processes of ependymal cells.
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  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 144 (1974), S. 101-122 
    ISSN: 1432-0568
    Keywords: Subcommissural organ ; Periodically structured bodies ; Vascular permeability ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Capillaren des Subcommissuralorgans (SCO) und deren Umgebung wurden an 38 adulten Sprague-Dawley- und an 6 adulten Wistar-Ratten nach Perfusionsfixierung im Elektronenmikroskop untersucht. Saure Mucopolysaccharide wurden mit Alcianblau und Rutheniumrot, Glykoproteide mittels der Perjodsäure-Silbermethenamin-Reaktion nachgewiesen. Der Stofftransport in den Capillaren wurde mit Meerrettichperoxidase (MRP) als Tracer untersucht. Die subcommissuralen Capillaren besitzen ein ungefenstertes, vesikelarmes Endothel, das einer einfachen, durchgehenden Basallamina aufsitzt. In der Umgebung der Capillaren finden sich neben periodisch strukturierten Körpern (PSK) vereinzelt Basallamina-Labyrinthe und regellos angeordnete kollagene Mikrofibrillen. Mit der Perjodsäure-Silbermethenamin-Reaktion lassen sich Glykoproteide im Bereich der Basallamina und der nach außen anschließenden Intercellularspalten darstellen, vereinzelt auch — teils im Bereich der Basallamina, teils ihr eng angeschlossen — Gruppen parallel angeordneter, linearer Strukturen mit einem periodischen Streifenmuster. Saure Mucopolysaccharide sind nur in der lumenseitigen Glykokalyx des Capillarendothels nachweisbar. Der Aufbau der PSK aus Kollagenfilamenten erscheint sehr wahrscheinlich. Vermutungen zur Entstehung dieser hochgeordneten Strukturen werden vorgebracht. Die Traceruntersuchungen ergeben, daß unter normalen Bedingungen in den subcommissuralen Capillaren eine Blut-Hirn-Schranke (BHS) für MRP besteht, die im Endothel lokalisiert ist. Bei einem Teil der Sprague-Dawley-Ratten ist die Barriere geschädigt und der Tracer gelangt über cytopemptische Vesikel in Basallamina und Gefäßumgebung. Der Basallamina und den PSK kommt in solchen Fällen keine besondere Schranken- oder Verteilerfunktion zu. Offenbar bewirkt bei manchen Sprague-Dawley-Ratten die MRP-Injektion über die Freisetzung von endogenen biogenen Aminen aus Mastzellen eine Schädigung der BHS, was bei Wistar-Ratten nicht eintritt.
    Notes: Summary The capillaries of the subcommissural organ (SCO) and their adjacent structures of 38 adult Sprague-Dawley rats and 6 adult Wistar rats were examined in the electron microscope after perfusion fixation. Acid mucopolysaccharides were shown by Alcian Blue and Ruthenium Red, glycoproteins were identified by the periodic acid-silver methenamine technique. Horseradish peroxidase (MRP) was used as a tracer for vascular permeability. The subcommissural organ's capillaries are characterized by an unfenestrated, continuous endothelium, showing only few vesicles; the endothelium is surrounded by a single, continuous basal lamina. Adjacent to the capillaries wall there are “periodically structured bodies” (PSK), labyrinths of the basal lamina and irregularly arranged collagen fibrils. Glycoproteins are found in the basal lamina and within the intercellular clefts; in a few cases groups of parallel arranged, periodically banded linear structures are seen within or adjacent to the basal lamina. Acid mucopolysaccharides are found within the endocapillary layer of capillaries. It seems very likely that PSK represent an atypical arrangement of collagen fibrils. The formation of these structures is discussed. Under normal conditions, MRP, after intravenous injection, does not enter the perivascular space surrounding the capillaries of the SCO. A blood-brain barrier exists at the level of the capillary endothelium. In a few Sprague-Dawley rats MRP seems to alter the permeability of the capillaries. Reaction product of MRP is found within endothelial vesicles and the adjacent structures. It appears that the basal lamina and the PSK are not involved in the barrier mechanism or regulation of transport. In Sprague-Dawley rats intravenous injection of MRP seems to alter the blood-brain barrier by release of endogenous biogenic amines associated with mast cell degranulation. This effect is not observed in Wistar rats.
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  • 15
    ISSN: 1432-0568
    Keywords: Neurohypophysis ; Neuro-vascular contacts ; Neuro-glial synaptoid contacts ; Dehydration ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The posterior lobe of the hypophysis consists of neurosecretory nerve fibres and glial cells, both abutting on the perivascular space of sinusoidal capillaries. Nerve fiberes and glial cells are connected with each other by a high number of synaptoid contacts. Several ultrastructural changes following dehydration have been described by other authors. This study presents the data of some morphometric investigations on normal and dehydrated rats. The relative extent of neuro-vascular contacts is not contstant; it increases significantly from 52 (±2.8)% in normal rats to 67(±1.2)% in rats with a dehydration time of 3 days. Correspondingly the extent of glio-vascular contacts is diminished. In addition, water-deprived animals show a clear increase in the number of neuro-glial synaptoid contacts with 3.1 (±0.4) per square unit nervous tissue compared to 2.1 (±0.3) per Square unit in untreated controls. These results indicate a dynamic motility of neuronal and glial elements depending on functional conditions, as was found for the external layer of the median eminence. Furthermore there seems to be a relationship between secretory activity and the number of neuroglial synaptoid contacts.
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  • 16
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    Anatomy and embryology 145 (1974), S. 169-186 
    ISSN: 1432-0568
    Keywords: Renal innervation ; Rat ; Peripheral nerves ; Neuroeffector zones ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In der Rattenniere werden die muskelzellhaltigen arteriellen Gefäße und der juxtaglomeruläre Apparat innerviert. Blutgefäße mit Pericyten, porenhaltige Capillaren sowie die Tubuli der Rinde und des Markes werden nicht von Nervenfasern begleitet. Ganglienzellen wurden in der Rattenniere nicht beobachtet. Periphere Nerven mit einem ein-bis zweischichtigen Perineurium kommen im paravasalen Gewebe der Interlobar- und Arcuata-Arterien vor; sie enthalten neben zahlreichen marklosen Nervenfasern gewöhnlich auch 2–4 markhaltige. Nervenfaser-Bündel ohne perineurale Scheide finden sich im paravasalen Gewebe der Arcuata- und Interlobular-Arterien. Darüber hinaus sind in unmittelbarer Nachbarschaft der großen Arterien (Interlobar-, Arcuata- und Inter-lobular-arterien) und der Vasa afferentia marklose Nervenfasern und freie Axone vorhanden, die auch die proximalen Abschnitte der Vasa efferentia der subcapsulären und intermediären Rindenschicht begleiten. Im Nierenmark werden die juxtamedullären Vasa efferentia und die Arteriolae rectae innerviert; marklose Nervenfasern und freie Axone sind nur bis zur Außen-Innenstreifen-Grenze nachweisbar. Die Innervation der muskelzellhaltigen arteriellen Gefäße erfolgt durch aufgetriebene Axonabschnitte (Neuroeffektor-Zonen), die vorwiegend agranuläre Vesikel enthalten. Diese Strukturen liegen stets an der Grenze von Adventitia und Media bzw. Elastica externa; zwischen den glatten Muskelzellender Media wurden keine vesikelhaltigen Axonabschnitte gefunden. Als minimaler Abstand zwischen den vesikelhaltigen Axonabschnitten und den von einer Basalmembran umschlossenen glatten Muskelzellen (neuromuskuläre Distanz) wurden 600 Å gemessen. Die vorliegenden Ergebnisse werden mit den fluoreszenzmikroskopischen und histochemischen Untersuchungen über die adrenerge und cholinerge Innervation der Niere verglichen. Die sich aus diesem Vergleich ergebenden Probleme und funktionellen Konsequenzen für die Innervation der Niere sowie die Natur der cholinergen Fasern (afferente oder postganglionäre parasympathische Fasern) werden diskutiert.
    Notes: Summary The innervation of the rat kidney is defined by a system which supplies those arterial blood vessels whose walls contain smooth muscle cells and the juxtaglomerular apparatus. Vessels containing pericytes, or those vessels composed of an endothelium only, as well as the tubules of both the cortex and medulla, are not innervated. Furthermore, ganglion cells do not occur in the rat kidney. The nervous apparatus of the rat kidney consists of peripheral vegetative nerves, ensheathed by a perineurium, with 2–4 myelinated fibers running in the paravasal tissue of the interlobar and arcuate arteries, and of nerve bundles without a perineurial sheath in the paravasal tissue of the arcuate and interlobular arteries. Non-myelinated fibers and free axons occur in the immediate vicinity of the great arteries (interlobar, arcuate, and interlobular) and the vasa afferentia. Nerve fibers and free axons are also seen in the vicinity of only the proximal parts of those vasa efferentia which supply the cortical capillary plexus. The arteriolae rectae of the medulla, and their vasa efferentia, from which they arise, are innervated by non-myelinated fibers and free axons which accompany these arterial vessels only to the boundary of the outer and inner stripe of the outer zone of the medulla. The functional innervation of those vessels with smooth muscle cells results from neuro-effector zones which predominantly show agranular vesicles. These structures were never seen between the smooth muscle cells within the media; the minimum neuromuscular distance was 600 Å. The present findings are correlated with the lightmicroscopically demonstrated adrenergic and cholinergic innervation. The resultant problems and functional consequences of the innervation of the kidney, especially the nature of the cholinergic fibers (afferent or post-ganglionic parasympathetic fibers) are briefly discussed.
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  • 17
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    Acta neuropathologica 27 (1974), S. 201-213 
    ISSN: 1432-0533
    Keywords: Infantile Neuroaxonal Dystrophy ; Spheroids ; Perikaryon ; Electron Microscopy ; Membranous Profiles ; Dense Bodies ; Protein Syntheses
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Electron microscopic findings of a cortical biopsy from a four-year-old child suffering from muscular weakness and psychomotor retardation are presented. Morphological evidence obtained in this study suggests a unique pathogenetic mechanism underlying INAD. The spheroids appear to be caused by an accumulation of a macromolecular substance synthesized in the neuron and transported to the nerve endings. The abnormal substance initially takes the form of an amorphous material, it eventually aggregates into highly characteristic angulated membranous profiles. The selective involvement of the nerve endings, synapses and motor end plates in this disease suggests a derangement of the metabolic pathway in the synthesis or packaging of the neurotransmitters or their receptors.
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  • 18
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    Anatomy and embryology 144 (1974), S. 173-186 
    ISSN: 1432-0568
    Keywords: Hippocampus ; Neurogenesis ; Autoradiography ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summay The prenatal ontogeny of the hippocampus, including the anterior continuation and induseum griseum, was examined in the rat by means of tritiated thymidine autoradiography. The neurons of the anterior continuation formed between the 16th and 18th days of embryonic development. The neurons of the induseum griseum were formed on the 16th and 17th days of gestation. The pyramidal cells of ammon's horn were formed during the 16th, 17th, 18th, and 19th days of embryogenesis but were preceded by the large interneurons of the stratum lacunosum-moleculare which formed on days 15 and 16 of embryonic life. The granule cells of the superficial layers of the stratum granulosum formed during the 20th, 21st, and 22nd days of gestation.
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  • 19
    ISSN: 1432-0568
    Keywords: Motor nerve terminals ; Methylene blue stain ; Hindlimb muscles ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary With methylene blue stain, three morphological types of motor nerve terminals were distinguished in hindlimb muscles (extensor digitorum longus, semitendinosus, soleus, and tibialis anterior muscles) of rat. Type A terminals possess many long thin branches with numerous minute swellings, type C ones possess few and thick terminal branches with few large swellings, and type B ones possess intermediate characteristics. The frequencies of occurrence of these types are characteristic for each muscle and differ between different hindlimb muscles. Specifically, soleus muscle contains a much higher proportion of type B terminals than other hindlimb muscles, and the superficial part of tibialis anterior muscle contains a higher proportion of type A terminals and a lower proportion of type C ones than the deep part. The frequencies of occurrence of types A, B, and C terminals closely parallel the frequencies of “white”, “intermediate”, and “red” muscle fibers (as determined by a fat stain), respectively, in the different muscles. As also suggested previously for the diaphragm, it is concluded that three morphological types of motor nerve terminals each may innervate one of three types of muscle fibers.
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  • 20
    ISSN: 1432-0568
    Keywords: Pantothenic acid deficiency ; Corticotropin-releasing factor ; Corticoids ; Histologie ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In the outer layer of the rat median eminence “Gomori-positive” granules occur which are assumed to be the morphological correlate of the corticotropin-releasing factor (CRF). The present study was carried out in order to establish whether the amount of these CRF-granules is influenced by a pantothenic acid (PA)-deficiency, which is known to result in an inhibition of corticosteroid production. Female SPF Wistar rats were used. PA-deficiency was induced by PA-free nutrition and/or administration of the PA-antagonist Ω-methyl-PA. Corresponding experimental groups were given either tap water or a solution of 1% NaCl and 5% glucose in tap water to drink. In rats fed with a diet free of PA and in addition treated with Ω-methyl-PA a severe disturbance of the corticoid balance developed within 6 weeks. The corticosterone production was depressed to about 11–16% of the control values. The adrenal cortex showed necrotic changes which either involved the whole parenchyma or were confined to the inner zones. In those animals in which a subcapsular region, in its extent corresponding to the zona glomerulosa, remained intact, an augmentation of the CRF-granules was observed. In those animals, however, in which the whole adrenal cortex was damaged, the amount of CRF-granules did not increase. Administration of the 1% NaCl containing drinking fluid did not influence the augmentation of the CRF granules, but had a protective effect on the development of necrotic changes in the zona glomerulosa of the adrenal cortex. The findings show that a functional relationship exists between the inner zones of the adrenal cortex and the CRF-granules in the median eminence.
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  • 21
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    Anatomy and embryology 145 (1974), S. 223-226 
    ISSN: 1432-0568
    Keywords: Rat ; Liver ; Bile ducts ; Cilia ; Scanning Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Numerous cilia have been demonstrated by SEM in cells of rat perilobular and portal bile ducts and ductules. Generally these cilia appear as long, cylindrical evaginations of the plasma membrane. Some of them are so long that, curving and twisting at many points, they cross the ductal lumen. It has been suggested that they may be related to a continual mixing up and propulsion of the bile product down the biliary tree.
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  • 22
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    Anatomy and embryology 143 (1974), S. 215-222 
    ISSN: 1432-0568
    Keywords: Lung ; Stretch receptors ; Light microscopy ; Electron microscopy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Lappenbronchien (3./6.) (Durchmesser bei mittlerer Inspirationslage 500–700 μ) von männlichen und weiblichen Wistarratten wurden licht- und elektronenmikroskopisch untersucht. Diese Bronchien entsprechen im Wandbau den mittleren Bronchioli größerer Säugetiere. Freie, verzweigte lanzettförmige Terminalfasern werden im Bindegewebe der lamina propria beschrieben. Sie sind in das elastisch muskuläre System der Bronchuswand eingebaut. Die zugehörige markhaltige afferente Nervenfaser ist verzweigt und hat einen Durchmesser von 4–6 μ. Außerdem werden efferente motorische Endigungen an der glatten Bronchialmuskulatur beschrieben. Die freien lanzettförmigen und verzweigten Terminalfasern sind möglicherweise Dehnungsrezeptoren für den Hering Breuer Reflex.
    Notes: Summary In rats the 3rd to 6th bronchi, measuring 500–700 μ in diameter during inspiration, were investigated by light and electron microscopy. The histological appearance of these bronchi is comparable to that of medium sized bronchioles of larger animals. The branched and lanceolate terminals are associated with the connective tissue of the lamina propria and the smooth muscle cell layer. In this way the terminals are bound to the myoelastic system of the bronchial wall. The myelinated afferent fiber is branched and the diameter measures about 4–6 microns. Besides afferent nerve terminals these are numerous efferent endings on the smooth muscle basement laminae. It is supposed that the described receptor represents the pulmonary stretch receptor of the Hering Breuer reflex.
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  • 23
    ISSN: 1432-0568
    Keywords: Superior cervical ganglion ; Rat ; p-Chlorophenylalanine ; 5-Hydroxytryptamine ; Catecholamine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Wirkung von Parachlorophenylalanin (pCPA) auf die paraganglionären Zellen und sympathischen Ganglienzellen des Ganglion cervicale superius der Ratte wurde untersucht. pCPA beeinflußt die sympathischen Nervenzellen im Ganglion cervicale superius geringgradig. Es finden sich unspezifische Veränderungen des Golgi-Apparates und der Nissl-Schollen sowie eine Zunahme von Lysosomen. Bei langdauernder Behandlung degenerieren einzelne Ganglienzellen und Nervenfasern. Die paraganglionären Zellen sind bei Kontrolltieren durch “dense core vesicles” eines einheitlichen Typs charakterisiert. Im Laufe der pCPA-Behandlung finden sich degranulierte paraganglionäre Zellen. Die Degranulation der einzelnen Zellelemente ist jedoch variabel. Bei fluorescenzmikroskopischer Untersuchung zeigt sich nach pCPA-Applikation eine Verschiebung des Fluorescenzspektrums zum grünen Bereich hin. Die bei Kontrollen deutliche Gelbkomponente nimmt nach 6–12 Tagen ab und verschwindet schließlich nach 18–20 Tagen. Es wird diskutiert, ob die fluorescenzmikroskopischen Veränderungen aufgrund einer Hemmung der Serotoninsynthese oder aufgrund einer abgeschwächten Katecholaminsynthese entstehen.
    Notes: Summary The effect of parachlorophenylalanine (pCPA) on the paraganglionic and sympathetic nerve cells of the rat superior cervical ganglion was studied. pCPA influences the sympathetic nerve cells of the cervical ganglion to minimal extent. Unspecific changes of the Golgi apparatus and of the Nissl bodies as well as an increase in the number of lysosomes occur. An extended period of treatment causes degeneration of individual ganglionic cells and nerve fibers. The paraganglionic cells in control animals are characterized by dense core vesicles of an unitary type. During pCPA treatment degranulated paraganglionic cells are to be found. The degranulation of the individual cell elements varies. Fluorescence microscopic study after pCPA application shows a shift of the fluorescence spectrum toward green. The yellow component of the control group decreases after 6 to 12 days and disappears after 18 or 20 days. It is discussed whether the fluorescence microscopic changes are due to the inhibition of serotonine synthesis or to a decrease of the catecholamine synthesis.
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  • 24
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    Acta neuropathologica 30 (1974), S. 271-276 
    ISSN: 1432-0533
    Keywords: Intracranial Teratoma ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A massive congenital benign teratoma grossly replacing the cerebral hemispheres has been examined by light and electron microscopy. The tumor contained tissues derived from all three germ layers. The cerebellum showed morphological features suggesting a state of maturation equivalent to that of 20 to 25 weeks of gestation. The tumor is discussed in the light of present theories on the pathogenesis of teratomas.
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  • 25
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    Acta neuropathologica 27 (1974), S. 43-53 
    ISSN: 1432-0533
    Keywords: Oncocytes ; Adenohypophysis ; Pituitary Adenoma ; Secretory Granules ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A light and electron microscopic study was undertaken on 3 surgically removed non-tumorous adenohypophyses and 16 pituitary adenomas. Numerous oncocytes have been found in 2 non-tumorous adenohypophyses and in 6 pituitary adenomas including 1 chromophobe adenoma which was composed almost exclusively of oncocytes. Thus, it seems that the occurrence of oncocytes in the anterior pituitary cannot be considered a rare finding. The distinctive feature of oncocytes is the abundance of mitochondria in their cytoplasm. This alteration can be so extensive that the entire cytoplasm is filled with mitochondria leaving only a small area for the remaining cytoplasmic organelles. Oncocytes arise from adenohypophysial cells. This transformation is gradual and is not restricted to one particular cell type. In the early phases of development of oncocytes the secretory granules are well preserved. Thus, hormone secretion is presumably maintained. It seems conceivable, however, that in the more advanced phases of evolution of oncocytes, when the secretory granules decrease in number, hormone production is diminished or stopped. Further investigations are, however, required to elucidate in detail the functional activity of oncocytes. It remains to be established whether mitochondrial accumulation is principally due to increased formation or delayed breakdown. As some mitochondria show signs indicating division it appears that multiplication of mitochondria is the underlying mechanism resulting in their significant increase. However, the possibility cannot be excluded that the life span of mitochondria is prolonged and mitochondrial longevity plays an important role in causing transformation of adenohypophysiocytes into oncocytes.
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  • 26
    ISSN: 1432-0533
    Keywords: Progressive Multifocal Leukoencephalopathy ; Hirano Bodies ; Papova Virus ; Paramyxovirus-like ; Nuclear Bodies ; Electron Microscopy ; Neurofibrillary Tangles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We have identified three structures that have not previously been reported in electron microscopic examinations of brain from patients with PML: 1. coiled nuclear bodies that may possibly represent tubular paramyxovirus nucleocapsids, 2. Hirano bodies and 3. Neurofibrillary tangles. The paramyxovirus-like material is interesting in view of reports of a transition between nuclear bodies and tubular paramyxovirus nucleocapsids and because of a possible interaction between syncytiogenic paramyxoviruses and Papova viruses in the pathogenesis of SSPE and PML. A study of the Hirano bodies in this case, taken in conjunction with the findings of others leads us to believe that these structures are formed from an overgrowth of neurofilaments. The presence of tangled masses of neurofilaments in the processes of neurons also seen in the present case is consistent with this hypothesis.
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  • 27
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    Acta neuropathologica 28 (1974), S. 93-103 
    ISSN: 1432-0533
    Keywords: Hexachlorophene Intoxication ; Toxic Encephalopathy ; Optic Nerve Necrosis ; Cerebral Edema ; Status Spongiosus ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This is the first report of neuropathologic findings following oral ingestion of hexachlorophene in the human. The patient was a 7 year old boy who accidentally ingested 45 ml (approx.) of pHisoHex (hexachlorophene).Toxic reactions included nausea, vomiting, anorexia, diarrhea, decrease in visual acuity, blurred vision blindness, somnolence and disorientation. He developed cardiac arrhythmia, fever, isoelectric EEG and finally respiratory and cardiac arrest 61 h after admission. Autopsy findings showed interstitial myocarditis, pneumonitis and acute bronchiolitis. The brain was edematous. Light microscopy revealed mild diffuse vacuolization of white matter, occasional neuronal degeneration, most prominent on deepest layers of the visual cortex. Disintegration of myelin sheaths and necrosis of axon cylinders were present throughoutoptic pathways. Electron microscopy revealed large, empty extracellular and intramyelinic spaces formed by splitting and separation of the myelin lamellae. These changes are known to occur in experimental animals intoxicated with hexachlorophene, triethyltin, isonicotinic acid hydrazide and cuprizone. However, with respect to hexachlorophene, the localization of lesions to be optic pathways appears to be dependent upon an oral route of administration.
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  • 28
    ISSN: 1432-0533
    Keywords: Neuroaxonal Dystrophy ; Infantile Autonomi Nervous System ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The autonomic nervous system is studied by electron microscopy for the first time in two siblings born of North African consanguineous parents and affected by infantile neuroaxonal dystrophy. The changes already reported in dystrophic axons of the central and peripheral nervous system, are seen in the myenteric plexus of rectum mucosa. The authors stress the diffuse involvement of the nervous tissue in this degenerative disorder of still unknown nature.
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  • 29
    ISSN: 1432-0533
    Keywords: Craniopharyngioma ; Tissue Culture ; Electron Microscopy ; Enzyme Histochemistry ; Keratine ; Enamel ; Rosenthal Fibers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Electron optical and enzyme histochemical investigations carried out on four craniopharyngiomas and their tissue cultures demonstrated that the tumour elements are keratinizing epithelial cells, plenty of tonofilaments, glycogen granules, mitochondria and desmosomes. Their ultrastructural and histochemical characteristics are the same in every part of the tumour (solid; cystic; “adamantinoma-like”). In the keratinizing cells, the reactions for non-specific esterases were high positive. The ultrastructural characteristics of the tumour cells grownin vitro are the same as thosein situ; the cells remain attached to one another by desmosomes and retain their capacity to produce keratine. This therefore seems to be a primary characteristic of the tumour cells and not a secondary dysmetabolic disturbance. Calcium was found onlyin situ. That the tumour cells may produce enamelin situ seems to be possible, but it could not be confirmed with certainty. The glial proliferation which is always presentin situ, is reactive and not neoplastic; thein vitro new built cell colonies consist only of epithelial elements.
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  • 30
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    Acta neuropathologica 29 (1974), S. 45-55 
    ISSN: 1432-0533
    Keywords: Experimental Neural Tumours ; Ethylnitrosourea ; Electron Microscopy ; Lysosomes ; Acid Phosphatase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A single intravenous injection of 30 mg of N-ethyl-N-nitrosourea per kg of body weight was administered to pregnant BD-IX rats on the 15th day of gestation. The neural tumours which developed in 97.5% of the offspring were gliomas and schwannomas. The demonstration of acid phosphatase in the neoplastic and reacting cells of these tumours was carried out at fine structural level. The enzyme activity was localised in lysosomes and in the innermost cisternae of the Golgi complexes. High acid phosphatase activity was related not only to degeneration, necrosis and phagocytosis but also to cellular differentiation and anaplasia.
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  • 31
    ISSN: 1432-0533
    Keywords: Steele-Richardson-Olszewski Syndrome ; Progressive Supranuclear Palsy ; Neurofibrillary Tangles ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The neurofibrillary tangles found in the neurons of a case of Steele-Richardson-Olszewski syndrome were studied by electron microscopy. Both the flame-shaped and globose type of tangles were present. The neurofibrillary tangles were composed of bundles of straight tubules measuring approximately 150 Å in diameter. This ultrastructural appearance of the tangles in Steele-Richardson-Olszewski syndrome is different from the appearance of tangles found in other neurological disorders and is probably indicative of intraneuronal accumulation of a new type of fibrous protein.
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  • 32
    ISSN: 1432-0533
    Keywords: Cholesterol Inhibitors ; Cerebrum ; Neuronal Inclusions ; Oligodendroglial Degeneration ; Rat ; Abnormal Sterols
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Wistar strain of rats received daily intraperitoneal or oral administration of Triparanol, 250 mg per kg of body weight or 20,25-diazacholesterol either 30 mg or 60 mg per kg of body weight starting at the age of 5 days old. Prominent intracytoplasmic osmiophilic inclusions identical to those found in the rats treated with AY9944 (Suzukiet al., 1973) and degeneration of myelin sheaths and oligodendroglia were seen in the myelinating white matter of rats sacrificed after 3, 6, and 9 injections of Triparanol. In diazacholesterol-treated animals, a few identical inclusions were seen in the cortical neurons but only slight changes were seen in oligodendroglia. Biochemical analysis of the brains of the rats receiving Triparanol revealed a large accumulation ofΔ 7,24-cholestadiene-3β-ol and lesser amounts of desmosterol. The brains of the animals treated with diazacholesterol revealed massive accumulation of desmosterol and a minor sterol component, probablyΔ 5,7,24-cholestatriene-3β-ol. Since AY9944, which results in a massive accumulation of 7 dehydrocholesterol (Δ 5,7-cholestadiene-3β-ol) and two other sterols,Δ 7,24-cholestadiene-3β-ol andΔ 5,7,24-cholestatriene-3β-ol, will produce identical neuropathological lesions to those seen in Triparanol treated animals, and since the lesion produced in diazacholesterol treated animals was very slight, there appears to be a correlation between the presence of sterols with a double bond at the 7-position and neuropathological lesions in young rats.
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  • 33
    ISSN: 1432-0533
    Keywords: Polyneuropathy Associated with Adie's Syndrome ; Sural Nerve ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The sural nerve of a woman of 35 with chronic polyneuropathy and Adie's syndrome was examined by electron microscopy. Myelinated nerve fibres were absent and there was marked reduction in the number of unmyelinated fibres. Onion bulb formation was not observed. Collagen fibres occupied the intercellular spaces.
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  • 34
    ISSN: 1432-0533
    Keywords: Experimental Neural Tumours ; Ethylnitrosourea ; Electron Microscopy ; Thiamine Pyrophosphatase ; Adenosine Triphosphatase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structural localisation of thiamine pyrophosphatase and adenosine triphosphatase was carried out in gliomas and schwannomas induced transplacentally by N-ethyl-N-nitrosourea. The activity of thiamine pyrophosphatase was observed in the Golgi complexes and appeared to be directly related to cellular differentiation and reactive changes. The Mg2+-dependent adenosine triphosphatase was localised at the cell membrane, in the pinocytotic vesicles of various cells and in the basement membrane of some capillaries. This enzyme, showing high activity in differentiated cells, indicated the activity of membrane-bound cellular transport.
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  • 35
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    Acta neuropathologica 29 (1974), S. 211-222 
    ISSN: 1432-0533
    Keywords: Experimental Gliomas ; Ethylnitrosourea ; Electron Microscopy ; Virus-like Particles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Two unusual, intracytoplasmic structures, resembling viruses, are described in experimental gliomas which were induced transplacentally on the 15th day of gestation in BD-IX rats by a single intravenous injection of 30 mg of N-ethyl-N-nitrosourea per kg of body weight. These structures are tubules within the lumen of the endoplasmic reticulum and large coated vesicles in the Golgi region. The tubules are of indeterminate length and have inner and outer walls of 9–11 nm and 20–22 nm respectively. The large coated vesicles are 80–90 nm in diameter and their outer surface is covered by regular, equidistant spikes of 12–15 nm in length. The vesicles are closely related to the Golgi complexes, from which they appear to originate. The intracisternal tubules and large coated vesicles share certain morphological features both with viruses and with normal cell organelles. The origin and significance of these structures are discussed.
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  • 36
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    Acta neuropathologica 30 (1974), S. 315-328 
    ISSN: 1432-0533
    Keywords: Human Adenovirus Type 12 ; Sprague-Dawley Rats ; Intracerebral Inoculation ; Medulloepitheliomatous Neoplasm ; Giant Tumor Cells ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Solid medullary brain and spinal cord neoplasms developed in all 10 offspring of an outbred Sprague-Dawley rat, between 37 and 99 days after a single postnatal (within 24 hrs) inoculation of 0.05 ml of human adenovirus type 12, 103.5–104.5 TCID50 HeLa cells/0.1 ml in the left frontal lobe. Seven rats developed multicentric neoplasms in both hemispheres and in peri-aqueductal areas of the brain stem, one of which was associated with an incipient spinal cord tumor in the sacral segment. One rat developed a solid tumor involving the right parieto-occipital region. The remaining two cases were solid spinal cord tumors arising from the dorsal half of the thoracolumbar segments. The remarkably uniform microscopic appearance was designated as a counterpart of human embryonic neuronal neoplasms. Characteristic neuronal and multinucleated giant cells emerged throughout the tumor tissue with argentaffine, neurofibril-like cytoplasmic expansions and a unique cilium (a 9+0 pattern of tubules) associated with a pair of centrioles. This cilium morphology was also a hallmark of the majority of tumor cells that formed characteristic pseudorosettes. The occasional emergence of two sets of cilia and centrioles in monstrous cells suggested probable modes of cytogenesis in relation to cessation of abnormal cell division.
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  • 37
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    Acta neuropathologica 30 (1974), S. 33-41 
    ISSN: 1432-0533
    Keywords: Organic Mercury Compound ; Late Pathological Changes in Peripheral Nerves ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Wistar strain of male rats of 100–110 g were used, 5 for an experimental and 5 for control group. 1 mg of organic mercury (methyl methylmercuric sulfide: CH3HgSCH3) was given by mouth each day for 10 days (total dose 9–10 mg) to the experimental group. 600 days afterwards the experimental and control rats were killed. Only the peripheral nerves showed changes, small myelinated nerve fibres with thick myelin sheaths in groups. Around these fibres occurred extremely small myelinated nerve fibres and isolated large unmyelinated fibres, and appeared to be regenerated fibres. Destruction of myelin sheaths and cavity formation in the axons were observed in these fibres. The changes in the axons were remarkable at the nodes of Ranvier.
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  • 38
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    Acta neuropathologica 30 (1974), S. 11-24 
    ISSN: 1432-0533
    Keywords: Ataxia ; Rabbit ; Degeneration ; Cochlear Nuclei ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary This hereditary animal ataxia is selective in its sites of involvement within the nervous system, which include principally the central cerebellar, vestibular and cochlear nuclei. Ultrastructural detail has been described for central cerebellar and vestibular nuclei. Herein the cochlear complex of 18 rabbits with this ataxic condition (ax/ax from the strain AX of the Jackson Laboratory) have been examined. The gene is a lethal one, but the animals were used before they became moribund and between 7 and 57 days after the onset of symptoms. By light microscopy nine cell types (Osen, 1969a, b; 1970) have been identified in the cochlear nuclei of the cat. That distribution can also be identified in electron micrographs of rabbit cochlear nuclei, providing there is a singular opportunity to compare cellular vulnerabilities within the ataxic condition, and establish the principal features of associated neuropil alterations. The cochlear nuclei, cerebellar cortex and central nuclei, and the vestibular nuclei, arise from the ependyma of the rhombic lip of the fourth ventricle, making them close allies in their genetic origins. Pathological alterations were evident in scattered neurons from all nuclear sources by 7–15 days following symptom onset. At 15 days the number of altered neurons evident in electronmicrographs had increased markedly, cells becoming involved at a more rapid pace than those already affected could be removed. Much glycogen is evident from 7 days onwards in both neuropil and neurons. It occurs in considerable amounts in astrocytic processes and less abundantly in endbulbs and somata. By 20 to 25 days spongioform changes in neuropil are prominent, and thereafter the extracellular spaces coalesce to produce a lacunar appearance showing little glycogen. It would appear, therefore, that all neuron types, the endbulbs, and the astrocytic processes are markedly involved simultaneously in the spongioform transformation which features this type of ataxia. Involvement of cochlear nuclei only differs in pathological detail from that found at the other involved sites, and the differences seen relate principally to the architectonics of the nuclei, including size and density of the packing of contained elements.
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  • 39
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    Acta neuropathologica 30 (1974), S. 155-173 
    ISSN: 1432-0533
    Keywords: GM1-Gangliosidosis ; Glycoproteins ; β-Galactosidase ; Lysosomal Disease ; Electron Microscopy ; Genetics of GM1-Gangliosidosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Post-mortem studies on a 6-year old boy with GM1-gangliosidosis, Type II revealed no evidence of accumulation of residual bodies nor of gangliosides or glycoproteins in liver and spleen. In brain tissue the ganglioside GM1 accounted for 70% of the ganglioside fraction and ganglioside-NANA was increased 3.6 fold over controls. In addition, the brain tissue contained large amounts of glycoprotein, glycoprotein derived galactose being increased 2.5 times. The neuronal accumulation of tertiary lysosomes exhibited a characteristic distributional pattern: in general the large neuronal perikarya were more consistently involved with the exception of the motor cells of the cranial nerve nuclei, III, IV, and VI. In addition to characteristic MCB's, the nerve cells contained residual bodies with a granulo-floccular matrix, presumed to represent glycoproteins. The distribution of the mutant gene was studied among 30 blood relatives of the proband at risk and 6 carriers could be ascertained on the basis of a reduced leukocytic β-galactosidase activity. The partly purified enzyme from the patient's liver revealed 20% activity as compared to that of normal controls. All three fractions obtained by DEAE cellulose column chromatography exhibited markedly reduced activity at pH 3.6, but nearly normal activity at pH 6.6. The reduced activity corresponded to the B component of the enzyme as shown by electrophoretic separation. It is pointed out that this case cannot be diagnosed as “generalized gangliosidosis” for the process of ganglioside accumulation was restricted to nervous tissue.
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  • 40
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    Acta neuropathologica 30 (1974), S. 189-196 
    ISSN: 1432-0533
    Keywords: Lafore Bodies ; Polysaccharidosis ; Electron Microscopy ; Epilepsia ; Histochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Cerebral biopsies of three patients aged 22, 18 and 16 years with myoclonic epilepsy contained Lafory bodies. Two were a brother and sister of consanguineous parents. The Lafora bodies occurred in most neurons but not in glial cells. The ultrastructure of these bodies showed a fibrillar and granular material in the perikaryon and neuropile. In some neurons small Lafora bodies were delimited by a double membrane, suggesting that in early phases they have a membrene which disappears when they become more developed. Other non-specific neuron alterations are described. One of the cases presented in the liver PAS positive bodies of a structure different from the Lafora bodies.
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  • 41
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    Acta neuropathologica 27 (1974), S. 25-32 
    ISSN: 1432-0533
    Keywords: Experimental CNS Tumours ; Nitrosomethylurea ; Ethylnitrosourea ; Primary Cultures ; Tumour Classification ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary By means of the explant technique a series of primary tumours induced by methylnitrosourea (MNU) or ethylnitrosourea (ENU) in the brain of rats were cultured in vitro. The morphology of isomorphic oligodendrogliomas, astrocytomas, glioblastomas and sarcomas under in vitro conditions is described. All these neoplasias show a very distinct morphological picture and growth behaviour, thus permitting their classification. Most of the tumours tend to anaplastic changes during longer cultivation, but in some cases, preferably in well differentiated gliomas, the cytological properties are maintained even during longterm cultivation. The role of anaplasia and intermingling of different neoplastic cell types in experimental tumours are discussed.
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  • 42
    ISSN: 1432-0533
    Keywords: Allergic Encephalomyelitis ; Organ Culture ; Brain ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Experimental allergic encephalomyelitis (EAE) developed in 15 of 30 rats injected with a mixture of Freund's adjuvant and homogenized guinea pig brain, and killed after 6–29 days. The incidence and severity of the disease increased with time after inoculation and in 2 animals involvement of the epiphysis, not previously reported in EAE, was detected. Toxic effects on cells in cultured adult rat cerebellar cortical tissue were produced by exposure for 24 h to the sera of rats killed 12–29 days after inoculation either with the antigenic suspension or with adjuvant alone. Severe toxicity to axons (widespread fragmentation) was produced only by the sera of animals injected with antigenic inocula and killed 17–29 days later. Severe axonal toxicity was not, however, correlated with the presence of EAE in the rats from which the sera were taken. It was not possible to assess myelinotoxic effects in the system used. It is suggested that the organ culture technique may detect the presence in the sera of inoculated animals of toxic principles which, owing to the blood-brain barrier, do not normally contribute to the pathogenesis of EAE.
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  • 43
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    Acta neuropathologica 27 (1974), S. 1-10 
    ISSN: 1432-0533
    Keywords: Leprosy ; Lepromatous ; Axonal Bacillation ; Schwann Cells ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary M. leprae bacilli in nerves of 3 patients with lepromatous leprosy were found in the axoplasm of myelinated and unmyelinated nerve fibers. Axonal bacillation occurred in as much as 2% of myelinated axons. Bacilli within Schwann cells were a more common finding in lepromatous leprosy that intra-axonal bacilli. Intra-axonal bacillation probably represents a late stage phenomenon in lepromatous leprosy. Intra-axonal bacilli may contribute to the dissemination of leprosy by migration of bacilli within the axon, and may contribute directly to nerve fiber destruction.
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  • 44
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    Acta neuropathologica 27 (1974), S. 69-82 
    ISSN: 1432-0533
    Keywords: Chronic Nerve Compression ; Median Nerve ; Guinea-Pig ; Electron Microscopy ; Degeneration ; Regeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In guinea-pigs with chronic median nerve compression at the wrist the electron microscopic changes at level of the lesion and both proximal and distal to it have been studied. At the level of the lesion in animals with prolonged motor latency there was a loss of large myelinated fibres. Remaining large fibres had disproportionately thin myelin sheaths or were demyelinated. Regenerating clusters containing myelinated fibres were present. Evidence of degeneration and regeneration of unmyelinated fibres was present in the more severely affected nerves of this group. Distal to the wrist myelinated fibre density recovered, with regenerating clusters and many axons having disproportionately thin myelin sheaths. Midforearm and upper arm levels were normal. In nerves in which no muscle response to electrical stimulation could be recorded in the palm, a few fibres devoid of myelin remained at the wrist. Immediately proximal to it myelinated fibres were rare, the main feature being Schwann cells containing axons devoid of myelin some of which were degenerating. Degeneration of myelinating fibres within regenerating clusters was seen. At the mid-forearm level large myelinated fibres were reduced and increased numbers of regenerating clusters were seen. Evidence of regeneration of unmyelinated fibres was found. The upper arm was normal.
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  • 45
    ISSN: 1432-0533
    Keywords: Myxopapillary Ependymoma ; Tissue and Organ Culture ; Electron Microscopy ; Basement Membrane
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Explants of a myxopapillary ependymoma were grown on collagen-coated coverslips and in organ culture systems using gelfoam sponge matrices and Millipore filter platforms. The tumor cultured on collagen-coated coverslips initially exhibited the cytologic features of simple uni- and bipolar glial cells and later developed an epithelial-like pattern. Delicate branching of argyrophilic cell processes was demonstrated in Bodian preparations. In organ cultures, the tumor architecture was well preserved for approximately 4 weeks, and mitotic figures were present. Invasion of the sponge foam matrix was seen. Later cultures demonstrated progressive perivascular sclerosis and hyalinization. By electron microscopy, the tumor cells in organ culture systems retained the major fine structural characteristics of the original neoplasm up to 27 daysin vitro. The most striking feature in the late stages was the extensive increase and reduplication of basement membrane material, which appeared related to the increase of collagen fibrils in the extracellular space.
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  • 46
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    Acta neuropathologica 27 (1974), S. 247-256 
    ISSN: 1432-0533
    Keywords: Werdnig-Hoffmann's Disease ; Electron Microscopy ; Muscle Biopsy ; Myotube-like Cells
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An ultrastructural study was carried out on muscle biopsies of 7 children with Werdnig-Hoffmann's disease. The muscle fibres were classified into 3 categories: 1. Muscle cells of normal diameter without any distinct or only slight changes. 2. Small muscle cells with a large central nucleus with the appearance of myoblast at a later stage of development. 3. Cells resembling myotubes containing in a common basement membrane two to four cells at different stages of maturation. Myoblast and myotube-like cells seemed to resemble foetal muscle fibres. Such fibres appear to represent an arrest in maturation rather than muscle atrophy.
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  • 47
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    Acta neuropathologica 28 (1974), S. 25-35 
    ISSN: 1432-0533
    Keywords: Chronic Lead Intoxication ; Rat ; Ultrastructure ; Microglia ; Pericytes ; Monocytes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Wistar rats of both sexes and the same litter were exposed to chronic lead intoxication from birth untill sacrifice 9 months later. Lead was administered as 0.4% solution of lead nitrate in drinking water. Samples from the parietal brain cortex were examined electron microscopically following intracardiac perfusion with paraformaldehyde-glutaraldehyde solution. Similar changes were observed in the microglial cells and the vascular pericytes whereas all the other tissue elements appeared intact. Both cell types hypertrophied, the microglia assumed characteristic spindle or rod shape, the cell organelles increased, the microglial endoplasmic reticulum widened strongly and a large number of lipid inclusions appeared. The latter consisted of large lipid droplets of varying size and shape, containing multiple zones of low density, and a dense component with a coarse granular structure. The similarity in the response of both cell entities to the lesion as well as some probable functions of microglial cells and their relationship to vascular pericytes are discussed.
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  • 48
    ISSN: 1432-0533
    Keywords: Jimpy Mouse ; Electron Microscopy ; Mouse Mutant ; Myelination ; Axonal Growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A quantitative study of the myelination and axonal growth in the corpus callosum and posterior columns of the spinal cord in the Jimpy mouse gave the following results: The reduction in the number of myelinated fibers is much more important in regions with late myelination, e.g. corpus callosum and pyramidal tracts than in the previously myelinated fascicles of Goll and Burdach. There is an important delay in the increase in volume of axons particularly within the structures of late myelination. The importance of the lacking axonal growth in relation to myelination is discussed.
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  • 49
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    Acta neuropathologica 30 (1974), S. 73-84 
    ISSN: 1432-0533
    Keywords: GM1 Gangliosidosis ; Friesian Calves ; Inborn Metabolic Error ; Histochemistry ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Histoenzymic and ultrastructural alterations in the brains of seven calves with GM1 gangliosidosis are described. A decreased oxidative enzyme activity in neurons was accompanied by an increase in acid phosphatase activity. Membranous cytoplasmic bodies were present in neurons and glia. The periodicity of the membranes was about 5.5 to 6.0 nm. Electron-dense, membrane-bound inclusions were present in perithelial cells. The lesions were compared with those of gangliosidoses in other species.
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  • 50
    ISSN: 1432-0533
    Keywords: Aseptic Meningitis ; Atheromatous Material ; Hypersensitivity ; Electron Microscopy ; Macrophages ; Pia-Arachnoid ; Granuloma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 500 mg of sterile pooled human atheromatous material was injected into the cisterna magna of 6 mongrel dogs. Repeated cisternal punctures were done at various intervals until sacrifice from 1 day to 28 days following injection. CSF was obtained for cell count, sugar, protein and analysis in the Technicon 6/60 which measured 14 additional chemical and enzymatic variables. All 6 animals showed a prompt cerebrospinal fluid (CSF) pleocytosis which largely subsided during the first 2 weeks after injection. Increased CSF protein content developed more slowly, but was more prolonged than the pleocytosis. There was a variable decrease in CSF sugar and increase in CSF lactate dehydrogenase, calcium and inorganic phosphorous. Light and electron microscopic studies showed an intense acute inflammatory reaction with marked phagocytosis of the foregin material, probably by arachnoidal cells and moderate edematous changes in the astrocytic processes at the site of injection. During the first 2 weeks after the injection the inflammatory reaction became chronic and the edematous changes in the medulla subsided.
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  • 51
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    Acta neuropathologica 30 (1974), S. 175-181 
    ISSN: 1432-0533
    Keywords: Reacting Astrocytes ; Phagocytosis ; Experimental Gliomas ; Ethylnitrosourea ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structure of reacting astrocytes in experimental gliomas has been described. These tumours were induced transplacentally by 30 mg of N-ethyl-N-nitrosourea per kg of body weight injected into the tail vein of pregnant BD-IX rats on the 15th day of gestation. In tumour-bearing animals astrocytes undergo striking morphological changes and show increased mitotic activity. Reacting astrocytes around gliomas display large, eccentric, irregular nuclei and the abundant cytoplasm contains an increased number of cell organelles. The most dramatic increase is in glial filaments: these form thick bundles at the periphery of the cells and in the processes which are frequently seen around demyelinated axons. Reacting astrocytes engulf and break down myelin sheaths: their remnants, lamellar inclusion bodies and lipid droplets, are present in the cytoplasm. Extravasated erythrocytes are also surrounded by and digested in reacting astrocytes. Numerous lysosomes could provide the necessary enzymes for the phagocytic activity of these cells.
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  • 52
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    Calcified tissue international 14 (1974), S. 283-289 
    ISSN: 1432-0827
    Keywords: Sodium fluoride ; Osteoporosis ; Bone ; Strength ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'utilisation thérapeutique de fluorure de sodium a été recommandée dans le traitement de diverses maladies osseuses ostéopéniques. Cet emploi est basé principalement sur les effects ostéosclérotiques bien connus du fluorure de sodium, mais on connait mal son effet sur la force de résistance osseuse. L'influence de diverses concentrations de fluorure de sodium sur la force de résistance osseuse de jeunes rats soumis à des régimes riches et pauvres en calcium a été étudiée. L'administration de fluorure de sodium augmente le diamètre osseux, indiquant une stimulation de la formation de l'os périosté, mais la force de résistance osseuse est réduite ou non modifiée par l'ingestion de fluor.
    Abstract: Zusammenfassung Die therapeutische Verwendung von Natriumfluorid ist für eine Anzahl von Knochenmangel-Krankheiten empfohlen worden. Die Empfehlungen basieren hauptsächlich auf den bekannten osteosklerotischen Wirkungen von Natriumfluorid; über dessen Effekt auf die Knochenstärke ist wenig bekannt. In dieser Arbeit wurde der Einfluß verschiedener Konzentrationen von Natriumfluorid auf die Knochenstärken von wachsenden Ratten mit hoher und niederer Calciumeinnahme untersucht. Die Verabreichung von Natriumfluorid erhöhte den Knochendurchmesser, was auf eine Stimulierung der Periostbildung hinwies, die Knochenstärke wurde jedoch durch Fluorideinnahme herabgesetzt oder nicht beeinflußt.
    Notes: Abstract The therapeutic use of sodium fluoride has been recommended in a variety of osteopenic bone diseases. The recommendations are based mainly on the known osteosclerotic effects of sodium fluoride and little information is available as to its effect on bone strength. The influence of various concentrations of sodium fluoride on bone strength in growing rats on high and low calcium diets was studied. The administration of sodium fluoride increased bone diameter, indicating stimulation of periosteal bone formation, but bone strength was reduced or not affected by fluoride ingestion.
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    Experimental brain research 21 (1974), S. 107-112 
    ISSN: 1432-1106
    Keywords: Preoptic units ; Thermosensitivity ; Mean firing rate ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Mean firing rates (per 10 sec) of preoptic neurons of the rat were recorded at normal temperature and after central warming and cooling. Thermosensitivity was determined according to the reactions of the mean firing rate. In compatibility with results from other animals we obtained the following percentages (52 neurons): 23% warm-sensitive, 13% cold-sensitive, 64% non-thermosensitive neurons. However, it turned out that a lot of interesting special effects are not taken into account, using exclusively the criterion “increasing/decreasing/constant mean firing rate”. Particularly we observed long lasting adaption processes and stationary non-linear effects as well as striking oscillations which were dependent on the thermal stimuli, while the mean interval value remained constant.
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  • 54
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    Naunyn-Schmiedeberg's archives of pharmacology 281 (1974), S. 175-196 
    ISSN: 1432-1912
    Keywords: Intestinal Absorption ; Basic Drugs ; Amidopyrine ; Antipyrine ; Solvent Drag ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Jejunal loops of anaesthetized rats were perfused with hypotonic, isotonic and hypertonic buffered solutions containing 14C-labelled amidopyrine and antipyrine at neutral and at acidic pH. The blood flow of the loop was maintained at an intermediate rate (0.7–1.0 ml min−1g−1). The water net flux was determined by means of polyethylene glycol as non-absorbable marker and amounted up to ±30 μl min−1g−1. 2. A positive water net flux (directed towards the blood) increased the appearance rate of amidopyrine and antipyrine by maximally 43.8 and 49.2%, a negative water net flux (directed towards the gut lumen) diminished it by 38.8 and 35.0%. 3. The experimental data were analysed by means of a kinetic model with the water net flux as independent variable and the epithelial permeability kF D , the serosal permeability k S F S and the sieving coefficient Φ=1−σ as absorption parameters. For antipyrine independent of the pH-value of the perfusion solution kF D was 0.123, and, for amidopyrine at pH 7 and pH 3 kF D was 0.231 and 0.091, respectively. k S F S was zero indicating that in this experimental arrangement the transfer of drug molecules to the serosal side was negligible. The sieving coefficient Φ amounted to 2.30 for amidopyrine and 2.15 for antipyrine at neutral pH. At acidic pH it amounted to 0.50 for amidopyrine and 1.44 for antipyrine. The hydraulic permeability of water was identical at neutral and acidic pH. 4. The high sieving coefficient for the two drugs at neutral pH is interpreted as indicating that water and lipophilic drug molecules interact within the lipid part of the cell membrane. At acidic pH the ionized drug molecules appear to permeate the cell membrane preferentially across other (presumably more hydrophilic) areas.
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    Naunyn-Schmiedeberg's archives of pharmacology 282 (1974), S. 195-212 
    ISSN: 1432-1912
    Keywords: Intestinal Blood Flow ; Intestinal Absorption ; d-Galactose ; Phlorizine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Jejunal loops of anaesthetized rats were perfused with buffered solutions (pH 6.8) containing d-galactose in two concentrations: below (100 μM) and above (100 mM) blood sugar concentration. The blood flow rate, the appearance rate (in the intestinal venous blood) and the disappearance rate (from the intestinal lumen) were determined simultaneously, the accumulation in gut tissue at the end of the experiments. 2. At constant intermediate blood flow the appearance rate and disappearance rate decreased with time. A decrease of the blood flow rate from about 1.9 to about 0.3 ml min−1 g−1 diminished both the appearance and the disappearance rate. An increase of blood flow from about 0.3 to about 1.9 ml min−1 g−1 did not increase the absorption rates; even a slight decrease was observed. 3. In the presence of phlorizine (2 mM) the absorption rates and the tissue accumulation of galactose is reduced. At constant intermediate blood flow the appearance and disappearance rate increased with time. A decrease of the blood flow rate from about 1.8 to about 0.3 ml min−1 g−1 diminished the appearance rate. An increase of the blood flow rate from about 0.3 to about 1.8 ml min−1 g−1 caused an increase of the appearance rate in contrast to the experiments without phlorizine. Therefore, the different blood flow dependence of the intestinal absorption observed with actively transported substances can be attributed to their non-passive component.
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  • 56
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    Naunyn-Schmiedeberg's archives of pharmacology 285 (1974), S. 175-184 
    ISSN: 1432-1912
    Keywords: Fenfluramine ; Rat ; Guinea Pig ; Phospholipidosis, drug-induced ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary After administration of the anorectic drug fenfluramine (40 mg/kg per day) to rats (s. c. or i. p.) and guinea pigs (p.o.) over periods of 2 to 11 weeks, electron microscopic examination was performed on lungs, liver, lymphatic tissues and peripheral blood of both species, and on adrenal glands and ovaries of rats. In rats, fenfluramine caused the following alterations (listed according to the duration of treatment): Formation of abnormal lamellated inclusions in lymphocytes and plasma cells of lymphatic tissues, appearance of “foam cells” in lung alveoli; formation of abnormal lamellated inclusions in corpus luteum, lymphocytes of peripheral blood, and in adrenal cortex. In guinea pigs, the same alterations were found in lymphocytes of spleen and peripheral blood, in hepatocytes and in lung. The present observations support the concept of a generalized phospholipidosis induced by amphiphilic compounds. The potency of fenfluramine to induce a lipidosis is, however, considerably less pronounced than that previously demonstrated for the anorectic drug chlorphentermine. This difference is suggested to be due mainly to the lower degree of amphiphilia of fenfluramine.
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  • 57
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    Psychopharmacology 37 (1974), S. 249-254 
    ISSN: 1432-2072
    Keywords: Chlorpromazine ; Rat ; Social Interaction ; Exploration ; General Motor Activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract When two animals were placed in a hole-board the number of headdips made by each rat was twice the number made when tested alone, but was the same for pairs of drugged (2 mg/kg chlorpromazine) and undrugged rats, and for pairs where only one rat was drugged. This contrasts with the reduction of headdipping produced by chlorpromazine in single animals. However, chlorpromazine still reduced general motor activity, regardless of whether the partner was drugged or not. The activity of the undrugged rats was affected by the partner's state and was lower when the partner was drugged.
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  • 58
    ISSN: 1432-2072
    Keywords: Rat ; Successive Discrimination ; Conditioned Avoidance Response ; Nerve Impulses ; α-Methyltyrosine ; Tetrabenazine ; l-Dopa
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The effect of the administration of l-Dopa, 10 or 100 mg/kg i.p., on the α-methyltyrosine methylester HCl (α-MT; 250+50 mg/kg i. p.) or tetrabenazine (TBZ; 2 mg/kg i.p.)-induced suppression of a successive discrimination-conditioned avoidance task has been studied. It was found that administration of the high l-Dopa dose resulted in a reversal of the α-MT- or TBZ-induced suppression of the avoidance behaviour, although the discrimination was lost. Restoration of the avoidance behaviour and the correct discrimination was obtained with the low l-Dopa dose after α-MT but not after TBZ. The difference in the behavioural response to l-Dopa after α-MT as compared to the response obtained after TBZ is discussed in terms of the availability of the catecholamines formed from l-Dopa for release by the nerve impulses. Biochemical determinations of brain noradrenaline and dopamine were made in parallel. Further, a simple and reliable method for the aquisition of a successive discrimination in the rat is described.
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  • 59
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    Psychopharmacology 39 (1974), S. 309-314 
    ISSN: 1432-2072
    Keywords: Avoidance ; Drug ; Psychotropic ; Rat ; Sidman Schedule ; Sulpiride
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Sulpiride, a new psychotropic drug with neuroleptic activity, was administered to rats in a Sidman avoidance schedule. Doses ranging from 1 to 80 mg/kg resulted in the animal receiving fewer shocks. This effect was not correlated with an increase of responding and seemed unrelated to the suppressing action abruptly observed at high doses (i. e. 150 to 200 mg/kg). These results differ from those classicaly obtained with other neuroleptics.
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  • 60
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    Psychopharmacology 35 (1974), S. 341-352 
    ISSN: 1432-2072
    Keywords: 6-Hydroxydopa ; Rat ; Behaviour ; Biogenic Amines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The influence of 6-hydroxydopa (6-HDP) injected into the lateral ventricles of rat brain on the behaviour of animals was examined. The level of noradrenaline (NA), 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) in discrete areas of the brain was also measured. 6-HDP was injected in a dose of 100 or 150 Μg into both lateral ventricles, or in a dose of 200 Μg into the right lateral ventricle. Immediately after 6-HDP injection, circling movements, convulsions, aggressive behaviour, and Stereotypic activity were seen. These components of behaviour were most obvious during the first hour after injection of 6-HDP. During one month after 6-HDP administration the behaviour of rats did not differ significantly from the behaviour of control animals, only very subtle differences in behaviour being seen. The dose of 150 Μg of 6-HDP caused aphagia and loss of body weigth during the first 5 days after treatment. 6-HDP also caused hypothermia. 20 min after administration of 200 Μg of 6-HDP a decrease of the NA level but no changes in the 5-HT level in the brain cortex were seen. The same changes were observed 1 month after 6-HDP treatment. The dose of 150 Μg of 6-HDP decreased the NA level in the brain cortex, cerebellum, mesencephalon and brain stem 5 days after treatment. 5-HT content was not changed and the 5-HIAA level was increased in the same brain areas. The dose of 100 Μg of 6-HDP, 2 weeks after the treatment decreased the content of NA in the brain cortex, cerebellum, hypothalamus and brain stem without changes in 5-HT content. 5-HIAA level was elevated only in the brain stem. It is concluded that 6-HDP is a long-acting potent depletor of NA in rat brain. There is a different sensitivity of brain areas to the depleting effect of 6-HDP. 6-HDP does not deplete the 5-HT content of discrete areas of brain but increases the level of 5-HIAA. 6-HDP causes distinct behavioural changes shortly after the treatment. It does not change the behaviour of rats between 1 and 30 days after its administration.
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  • 61
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    Psychopharmacology 36 (1974), S. 323-335 
    ISSN: 1432-2072
    Keywords: Methamphetamine ; Rat ; Conditioned ; Aversion ; Space ; Saccharin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Three experiments were performed on Sprague-Dawley derived rats in which 3.0 mg/kg, i.p., injections of methamphetamine were paired with either, (1) a distinctive spatial enclosure, i.e., either a black or gray portion of a shuttle box with discriminably different flooring, (2) the enclosure plus 0.1% saccharin solution availability in the home cage, or (3) the enclosure plus 0.1% saccharin solution availability in that area. Following three drug pairings which alternated with saline injections paired with a different enclosure or enclosure plus H2O availability, a choice of either spatial (1), or spatial plus gustatory stimuli (2,3) which included the original CS's, were presented under non-drug, non-injection conditions. Control groups received saline injections each day under identical conditions. No aversion to the enclosed area, which had been paired with the drug was demonstrated under (1), gustatory (P=0.005) but not spatial aversion was in evidence in the second paradigm, and spatial (P=0.01) and gustatory (P〈0.01) aversion was exhibited in the last study. It was concluded that subsequent aversion to distinctive spatial enclosures following methamphetamine injections was not as strong an effect as similar aversions to gustatory stimuli. Furthermore, the effect only obtained to neutral and not to preferred spatial areas at the dose level tested and in the apparatus used in those studies.
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  • 62
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    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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    Pflügers Archiv 350 (1974), S. 241-248 
    ISSN: 1432-2013
    Keywords: Cardiac Hypertrophy ; Diffusion Distance of Oxygen ; High Altitude ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In rats born and staying their whole life at a simulated altitude of 3500 m a severe cardiac hypertrophy develops which is most pronounced in the right ventricle. On histological sections muscle fiber and capillary densities were counted and the surfaces occupied by muscle fibers and capillaries in the slides were estimated. Mean muscle fiber diameter and half mean distance between capillaries (diffusion distance) were obtained in the heart ventricles and were compared with those of control animals. In both ventricles an increase of the mean muscle fiber diameter occurred (true hypertrophy), being more pronounced in the right ventricle. We cannot tell whether also hyperplasia of muscle fibers occurred or not. The diffusion distance in the left ventricle of rats exposed to hypoxia was about the same as in control animals but was shorter in the right ventricle. This indicates that the total number of capillaries is higher in both ventricles of rats born in the low pressure chamber (hyperplasia of the capillaries). The shortening of the diffusion distance in the right ventricle of rats born and living their whole life at simulated high altitude was on the average smaller than that of rats exposed to simulated high altitude later in life. The physiological importance of this observation is discussed.
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    Pflügers Archiv 351 (1974), S. 13-24 
    ISSN: 1432-2013
    Keywords: Hypothalamus ; Spike-Trains ; Correlogram/Periodogram ; Thermosensitivity ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Stationary spike-trains of preoptic neurons of the rat were submitted to a correlation- and spectral-analysis at normal temperature and after central warming and cooling. Correlograms and periodograms were computed which enable the elimination of stochastic signal components and the identification of the relevant periodic components. About one half of the analysed neurons showed periodic correlograms. The following three classes may be distinguished: Neurons which showed correlograms with periodicities at each applied thermal state, at only one or two thermal states and those with no recognizable periodicities at all. Relations between periodicity and the thermosensitivity of the neurons are discussed.
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    Experimental brain research 20 (1974), S. 181-192 
    ISSN: 1432-1106
    Keywords: Locus ceruleus ; Cerulo-cortical tract ; Ascending reticular fiber ; Rat ; Fink-Heimer method
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In order to demonstrate the ascending projection from the locus ceruleus by degeneration silver method, the nucleus was destroyed unilaterally in rats and the brains were stained by a modified Fink-Heimer method following various survival times. Additional experiments included the bilateral destruction of the locus ceruleus and the administration of 6-OH-DOPA. For the demonstration of degenerated terminals in the cerebral cortex it is essential to choose an optimal survival time of 4 or 5 days, keep the time of fixation below 1 week, and perform treatments with permanganate and with silver at 37°C. The trajectory and distribution of the cerulo-cortical tract as revealed by the silver degeneration methods is in agreement with the results of the histofluorescence method, with some minor differences. The ascending fibers run through Forel's tegmental fascicle, turn rostro-ventrally to the subthalamus, enter and cross the internal capsule, pass through the ventral part of the caudate-putamen and distribute to the entire cerebral cortex. The tract is mainly ipsilateral, though some fibers are crossing.
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  • 66
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    Archives of microbiology 98 (1974), S. 271-274 
    ISSN: 1432-072X
    Keywords: Proteus vulgaris ; Bacteriocin ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The intracellular development of a bacteriocin in a strain of Proteus vulgaris was investigated. Particles which resemble the bacteriocin make their appearance in the cell after 60 min induction with mitomycin C. At this stage they appear as broad bands of tightly-packed phage tail-like structures. With longer periods of induction the bands are disrupted to liberate individual phage tail-like particles.
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    Archives of microbiology 98 (1974), S. 311-329 
    ISSN: 1432-072X
    Keywords: Dictyostelium discoideum ; Inorganic Polyphosphate ; Electron Microscopy ; Enzymes ; Polyphosphate Metabolism ; Cellular Slime Mold ; Polyphosphatase ; Polyphosphate-ADP-Phosphotransferase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The concentration of inorganic polyphosphates in Dictyostelium discoideum was low in the amoebae. A ca 5-fold increase took place during the early stages of multicellular development and was followed by a decrease during the intermediate stages. Electron micrographs showed the presence of electron dense material in all parts of the differentiating cells. The substance was most frequently observed in various types of vacuoles. Two enzymes of polyphosphate metabolism were identified and studied in cell-free extracts: a polyphosphatase and a polyphosphate-ADP-phosphotransferase. No polyphosphate-glucose-phosphotransferase or polyphosphate-AMP-phosphotransferase activities were observed in the extracts. The specific activity of the polyphosphatase, pH optimum 7.6, was ca 30 nmol Pi·min-1·mg protein-1 at all stages of development. The enzyme activity was not inhibited by 0.01 M orthophosphate. The polyphosphate-ADP-phosphotransferase, pH optimum ca 7.7, was studied in the direction of ATP. The enzyme specific activities were very low, about 0.2 nmol P·min-1·mg protein-1, and rather constant during differentiation. The enzyme activity was inhibited by orthophosphate and by excess ADP. It was concluded that the polyphosphate-ADP-phosphotransferase did not contribute significantly to the formation of ATP during multicellular development, and that polyphosphate did not act as a phosphagen in the differentiating cellular slime mold. It was suggested that polyphosphate served as a phosphate store and as a means of regulating the intracellular orthophosphate concentration during development.
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    Archives of microbiology 97 (1974), S. 27-38 
    ISSN: 1432-072X
    Keywords: Mass Mating ; Electron Microscopy ; Cell Fusion ; Membrane Structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The process of mating reaction of Saccharomyces cerevisiae was studied by electron microscopy. Prior to the dissolution of the part of the cell walls separating the conjugating pair of cells, the thinning of the electron transparent layer of the cell wall occurs at the part toward which the nuclei are migrating. After the dissolution of the cell walls of the conjugating cells, the cell membranes become associated with each other, then to be broken and rejoined. The first diploid bud emerges from about the middle of the zygote. The morphological changes during the mating reaction are discussed in relation to the biochemical changes so far known.
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    Archives of microbiology 99 (1974), S. 281-294 
    ISSN: 1432-072X
    Keywords: Spirochete ; Artemia ; Brine Shrimp ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. A spirochete which occurs in tissues of the brine shrimp,Artemia salina, was studied by light microscopy and transmission electron microscopy. A total of seven infected shrimps were encountered. 2. Under darkfield illumination, most spirochete cells inArtemia blood were 6–13 μ long and 0.3–0.4 μ wide. Coiling was variable and often irregular. 3. When tissues of the maxillary gland (kidney) and nearby organs were examined by electron microscopy, spirochete cells were found in both extracellular and intracellular locations. These microbes possessed the ultrastructural features typical of members of the Order Spirochaetales: a) a slender protoplasmic cylinder (0.18 μ average diameter), b) axial fibrils (150 A average diameter), and c) an outer envelope or sheath (approximately 75 A thick). 4. Counts made of the number of axial fibrils evident in transverse sections of spirochete cells were consistent with the hypothesis that this spirochete has a 1-2-1 arrangement of axial fibrils. 5. Non-spiral forms were observed in the haemocoel and in the lumen of the maxillary gland.
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  • 70
    ISSN: 1432-0738
    Keywords: Alcohol, Ethyl ; Absorption ; Elimination ; Alcohol Oxidoreductases ; Hepatitis, Toxic ; Transaminases ; Glutamate Dehydrogenase ; Guinea Pig ; Rat ; Äthylalkohol ; Resorption ; Elimination ; Alkoholdehydrogenase ; Hepatotoxicität ; Transaminasen ; Glutamatdehydrogenase ; Meerschweinchen ; Ratte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die maximalen Blutalkoholkonzentrationen nach oraler Gabe von 6,4 g/kg Äthanol in Form einer 40%igen Lösung (v/v) betrugen bei nicht nüchternen Meerschweinchen 6,8±0,3 mg/ml, bei nicht nüchternen Ratten dagegen nur 2,1±0,2 mg/ml. An nüchternen Tieren führte eine orale Alkoholbelastung von 4,8 g/kg zu maximalen Blutalkoholspiegeln von 6,3±0,2 mg/ml bei den Meerschweinchen und 3,7±0,3 mg/ml bei den Ratten. Intravenös injizierter Alkohol (1 g/kg) wurde demgegenüber von beiden Species mit der gleichen Geschwindigkeit eliminiert (275 mg/kg · Std), und die auf das Körpergewicht bezogene ADH-Aktivität der Leber war bei den Meerschweinchen um 20% größer als bei den Ratten. Die Resorption von Äthanol erfolgt somit bei Ratten erheblich langsamer als bei Meerschweinchen. Dies dürfte darauf beruhen, daß konzentrierte Alkohollösungen die Magenentleerung der Ratte stark verzögern. Niedriger konzentrierte Alkohollösungen werden von der Ratte schneller resorbiert; jedoch waren auch nach Gabe von 10%igem Alkohol die maximalen Blutalkoholspiegel bei Ratten noch um 36% niedriger als bei Meerschweinchen. Bei den Meerschweinchen waren nach oraler Gabe von 4,8 bzw. 6,4 g/kg Äthanol die Serumaktivitäten der GOT, GPT und GLDH erhöht; ein Anstieg der SGOT trat schon nach 1,6 g/kg Äthanol auf. Demgegenüber kam es bei Ratten nach 6,4 g pro kg Äthanol p.o. nur zu geringfügigen Aktivitätserhöhungen der Serumtransaminasen, während die Serumaktivität der GLDH unverändert blieb. Vacuolige Degeneration war das morphologische Substrat der durch Äthanol bei Meerschweinchen und Ratten ausgelösten Leberschädigung. Während diese Veränderung bei Meerschweinchen bereits nach einer Äthanoldosis von 1,6 g/kg auftrat, wurde sie bei Ratten erst nach 6,4 g/kg beobachtet. Schlußfolgerung: Das Meerschweinchen ist für Untersuchungen zur Toxicität von Äthanol besser geeignet als die Ratte.
    Notes: Abstract In fed guinea pigs, an oral dose of 6.4 g/kg of ethanol given as a 40% solution (v/v) produced a maximal blood alcohol level of 6.8±0.3 mg/ml, whereas in fed rats, blood alcohol levels after the same dose did not exceed 2.1±0.2 mg/ml. Maximal blood alcohol levels in fasted animals after an oral load of 4.8 g/kg of ethanol were 6.3±0.2 mg/ml in guinea pigs and 3.7±0.3 mg/ml for rats. However, i.v. injected ethanol (1 g/kg) was eliminated at the same rate in both species (275 mg per kg · h), and ADH activity of the liver related to body weight was by 20% greater in guinea pigs than in rats. Therefore, absorption of ethanol occurs at a much slower rate in rats than in guinea pigs. This is possibly due to the fact that high ethanol concentrations strongly delay emptying of the rat stomach. Lowering the ethanol concentration accelerates absorption rate in the rat. However, even after gavage of a 10% solution peak levels of blood alcohol were still lower by 36% in rats than in guinea pigs. In guinea pigs, increased serum activities of GOT, GPT, and GLDH occurred after an oral dose of 4.8 g/kg or 6.4 g/kg of ethanol, respectively. SGOT already increased after 1.6 g/kg of ethanol p.o. After 6.4 g/kg of ethanol given to rats serum transaminase levels increased only slightly, and GLDH activity not at all. Vacuolar degeneration was the morphological substrate of ethanol-induced liver damage in guinea pigs and rats. In guinea-pigs, it occurred already after 1.6 g/kg of ethanol, whereas in rats only after 6.4 g/kg. In conclusion, the guinea pig seems to be better suited for research on alcohol toxicity than the rat.
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    Lung 150 (1974), S. 185-189 
    ISSN: 1432-1750
    Keywords: Paraquat Poisoning ; Morphology ; Electron Microscopy ; Light Microscopy ; Letal Course ; Human Lung ; Lung Fibrosis ; Proliferative Alterations ; Degenerative Alterations ; Pathogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Morphological alterations in the lungs of 3 cases of paraquat intoxication with prolonged lethal course (10, 11, and 25 days) are reported. Combined light-and electronmicroscopic studies reveal that 10 and 11 days after the ingestion of paraquat the endothelium of the occassionally congested capillaries is intact. The basal membranes have only scarce alterations. They are sometimes naked because of shadding of both types of pneumocytes with severe alterations, e.g. lipid accumulation in the cytoplasm. In the vast alveolar edema, red blood cells, some round cells, strands of fibrin, and lamellar cell debris are seen. There are also varying amounts of polymorphnuclear leucocytes and alveolar macrophages with many phagolysosomes and cytosegresomes. Fibroblasts with lipid droplets between the extensive RER form varying amounts of collagen fibrils in the alveolar and sometimes in the very edematous interstitial space. Sometimes surrounded by collagenous material, they thus devoured by macrophages. 25 days after paraquat intoxication a severe alveolar fibrosis, focal interstitial fibrosis, and areas with atelectasis are found. Due to artificial respiration and changed ventilation mechanics, there were large areas with hemorrhage and a honeycomb-like structure of the remaining lung parenchyma. The pathogenesis of the degenerative and proliferative lung alterations is briefly discussed.
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    Archives of microbiology 100 (1974), S. 145-162 
    ISSN: 1432-072X
    Keywords: Complex Flagella ; Fine Structure ; Electron Microscopy ; Optical Diffraction ; Flagellin ; Flagellar Motion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Zellen von Rhizobium lupini H 13-3 besitzen 5–10 peritrich inserierte komplexe Geißeln, deren Feinstruktur durch Hochauflösungs-Elektronenmikroskopie und lichtoptische Diffraktion analysiert wurde. Das Geißelfilament hat einen Durchmesser von 160 Å und besteht aus einem zylindrischen Kern (Durchmesser ca. 110 Å), der fest von drei Bändern einer helikalen Scheide umgeben ist. Die Scheidenbänder sind 49 Å breit, durch 49 Å-Intervalle voneinander getrennt und haben eine Steigung von 31°. Die komplexen Geißelfilamente bestehen aus einem 43 000-Dalton-Protein, das den Kern und die helikale Scheide aufbaut. Beide gehen übergangslos aus dem proximalen Geißelhaken hervor, der einen Durchmesser von 150 Å und eine Länge von 600 bis 800 Å hat. Die Diffraktionsanalyse des Geißelhakens zeigte eine helikale Grundanordnung von globulären Untereinheiten, die ein Oberflächengitter von 5 parallelen Schrauben (Steigung 29° bzw. 33°) bilden, von denen jede fast 11 Untereinheiten pro Helixungang trägt. Die komplexen Geißeln von R. lupini H 13-3 und Pseudomonas rhodos [Schmitt et al.: J. Bact. 117, 844–857 (1974)] sind ein neuer Typ von Bakteriengeißeln. Sie zeigen deutliche Übereinstimmung in der Feinstruktur, der festen Verbindung von helikaler Scheide und Geißelhaken sowie in der Fragilität ihrer Filamente; sie unterscheiden sich deutlich im Molekulargewicht der Flagellinmonomeren (43 000 bzw. 55 000). Zellen von R. lupini H 13-3 führen schnelle, vibrierende Translationsbewegungen aus. Mögliche Mechanismen der Bewegung komplexer Geißeln werden diskutiert.
    Notes: Abstract Cells of Rhizobium lupini H 13-3 possess 5 to 10 peritrichously inserted complex flagella, which were analyzed by high resolution electron microscopy and by optical diffraction. The flagellar filament has a diameter of 160 Å; it consists of a cylindrical core (diameter approximately 110 Å) surrounded by three close-fitting bands of a helical sheath. The helical bands are 49 Å wide, separated by axial intervals, 49 Å wide, and run at an angle of 31°. Complex filaments consist of a 43 000-dalton protein representing the core and the helical sheath. These originate from the proximal hook, which has a diameter of 150 Å and a length of 600 to 800 Å. The diffraction analysis of the hook showed a helical arrangement of globular subunits forming a surface of 5 parallel “small-scale” helices (pitch-angles 29° and 33°, respectively), each carrying almost 11 subunits per period. The complex flagella of R. lupini H 13-3 and Pseudomonas rhodos [Schmitt, et al.: J. Bact. 117, 844–857 (1974)] represent a novel type of bacterial flagella. There is agreement in their fine structures, in the intimate connection of the helical sheath and the core, and in the fragility of their filaments. Thery are clearly distinguished by the molecular weights of their flagellin monomers (43 000 and 55 000, respectively). Cells of R. lupini H 13-3 show fast, vibrating, translational motions. Possible mechanisms of complex flagellar motion are discussed.
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    Archives of microbiology 100 (1974), S. 307-328 
    ISSN: 1432-072X
    Keywords: Citrate Lyase ; Subunit Structure ; Electron Microscopy ; Reaction Inactivation ; Rhodopseudomonas gelatinosa ; Phototrophic Bacteria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. Citrate lyase (EC 4.1.3.6) from Rhodopseudomonas gelatinosa has been purified to homogeneity by protamine sulfate fractionation, chromatography on DEAE-Cellulose and gel filtration. The final enzyme preparation had a specific activity of 138 units per mg of protein and was purified 43-fold over the crude extract. Analysis of citrate lyase by sedimentation equilibrium experiments and gel filtration gave molecular weights of 530000 and 560000, respectively. 2. Electron microscopic investigations of negatively stained enzyme molecules and image analysis showed that citrate lyase is composed of six large and six small subunits; they are arranged in two hexagonal rings lying face to face, each containing, in alternating sequence, three large and three small subunits. The enzyme molecule is 160 Å in diameter and about 100 Å thick. 3. Treatment with sodium dodecylsulfate and mercaptoethanol dissociated citrate lyase into three proteins. Protein III (small subunit) had a molecular weight of 30000 and contained the pantothenate; protein II (large subunit) had a molecular weight of 61000; protein I (M r =97000) was probably an aggregate of II and III. 4. Based on the results obtained a model of citrate lyase was constructed. 5. Purified citrate lyase was obtained from R. gelatinosa in a deacetylated and largely oxidized form. The enzyme was activated by reduction with dithiothreitol (3 mM) and subsequent acetylation with acetic anhydride (1.75 mM). 6. The enzyme was subject to reaction inactivation, the extent of which depended on the concentration of Mg2+.
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  • 74
    ISSN: 1432-072X
    Keywords: Bdellovibrio bacteriovorus ; Spirillum serpens ; Freeze Fracture ; Electron Microscopy ; Ultrastructure ; Membrane Damage ; Organismic Associations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The freeze-fracture technique and electron microscopy have been used to demonstrate that localized damage is inflicted upon the cytoplasmic membrane of Spirillum serpens VHL within 20 to 30 min after the start of its association with Bdellovibrio bacteriovorus 109D. This damage is not observed in uninfected Spirillum cells, nor in infected cells within the first 10 min. This damage takes the form of a “blister” which, when viewed stereoscopically in electron micrographs, is seen to project toward the interior of the Spirillum cell. Shortly after its formation, the blister becomes elaborated into a series of ridges which may assume forms ranging from an elaborate spiral to a series of loops or knots. The formation of a blister is shown to involve both the inner and outer leaves of the membrane bilayer, and evidence is presented to indicate that the blister site corresponds to the site of attachment of the Bdellovibrio cell. The hypothesis is proposed that this ultrastructural damage is the cytological basis for the controlled and localized leakage through the cytoplasmic membrane into the periplasmic space of the Spirillum cell at locations adjacent to the Bdellovibrio cell. It is suggested that this localized membrane damage may be the ultrastructural basis for the high efficiency with which bdellowvibrios are known to incorporate cytoplasmic materials from the other bacteria in whose periplasmic spaces they develop.
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  • 75
    ISSN: 1432-2072
    Keywords: Rat ; Chlordiazepoxide ; Diazepam ; Extinction ; Avoidance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In a one-way avoidance task with rats, injections of Librium (chlordiazepoxide) following avoidance acquisition resulted in prolonged resistance-to-extinction of the avoidance response. This effect occurred regardless of whether the rats had had prior experience with Librium or whether they were naive with respect to the drug. The same results were found with the same task when low doses of Valium were used. However, at a higher dosage an “extreme reaction” of either no responding or a high number of responses to extinction occurred in the naive animals. The Librium and Valium effects were compared to similar effects obtained using ethanol and hashish resin. These results indicate that the novelty hypothesis as originally stated by Amit and Baum cannot be supported because experience with the drugs prior to avoidance training did not attenuate the drug effect on avoidance.
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  • 76
    ISSN: 1432-2072
    Keywords: LSD-25 ; UML ; 5-HT ; Brain ; Platelets ; Behaviour ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Factorial analysis of rat cerebral 5-HT values observed following intraperitoneal LSD-25 and UML (1-methyl-d-lysergic acid butanolamide) showed that the highly significant decrease induced by both drugs was independent of dose and that the effect of both drugs was the same. Increased platelet 5-HT values were also obtained with each drug. These findings suggest that the psychotomimetic effect of LSD-25 is not due to changes in cerebral 5-HT, since a relationship can probably be postulated between such an effect in man and the effect of LSD-25 on conditioned behaviour in the rat. It is also felt that the fact that these drugs decrease and increase cerebral and platelet values respectively may be of assistance in the interpretation of data relating to platelet 5-HT patterns in man under psychiatric conditions and during treatment with psychotropic drugs.
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  • 77
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    Psychopharmacology 37 (1974), S. 91-100 
    ISSN: 1432-2072
    Keywords: Ethanol ; Brain Serotonin Turnover ; Tolerance ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In rats treated acutely and chronically with ethanol, brain serotonin (5-HT) turnover was determined by measuring in the same animals the rate of accumulation of 5-HT and the rate of decline of 5-hydroxyindoleacetic acid (5-HIAA) in the brain after administration of the MAO inhibitor pargyline-HCl. In the acute study, 5-HT turnover was not altered after a single 4 g/kg oral dose of ethanol. In two separate studies, it was shown that chronic administration of ethanol in the form of a liquid diet for 32 days also did not alter brain 5-HT turnover, even when the rats had developed a significant degree of tolerance to the motor-impairing effects of ethanol. These results suggest that tolerance to ethanol is unrelated to any change in brain 5-HT turnover.
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  • 78
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    Pflügers Archiv 352 (1974), S. 115-120 
    ISSN: 1432-2013
    Keywords: Urate ; Reabsorption ; Loop of Henle ; Micropuncture ; Microperfusion ; Microinjection ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Reabsorption rates for urate in the loops of Henle were measured in superficial nephrons in the rat 1. under conditions of free flow, 2. using microperfusion and 3. by a microinjection technique. 1. Under conditions of free flow distally measured TF/PUA/TF/PIn-values varied between 0.51 and 0.38 in antidiuretic rats, depending on TF/PIn (UA = both uric acid and urate, In = inulin, TF/P = concentration in tubular fluid to plasma concentration). The corresponding values in samples from end-proximal tubules were 1.06 and in urine 0.19 (U/PUA/U/PIn). 2. In microperfusion experiments of Henle loops early distal recoveries of 2-C14 urate varied between 57 and 86%, depending on the flow rates (10–40 nl/min). 3. In microinjection experiments C14 recovery in urine was about 85% when tracer solution was microinjected into endproximal tubules. From these results we conclude: 1. The main site of urate reabsorption is located in the loops of Henle. 2. This reabsorption is highly dependent on flow rates. Increase of flow rate through Henle's loop decreases urate reabsorption.
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  • 79
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    Pflügers Archiv 352 (1974), S. 121-133 
    ISSN: 1432-2013
    Keywords: Urate ; Protein Interaction ; Uptake by Erythrocytes ; Renal Reabsorption ; Man ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Interaction of urate with human and rat plasma was studied by a dialysis technique at different temperatures. At 4° C a certain fraction of urate is bound to proteins. However, this fraction diminishes with increasing temperature and at 37° C only some 7–8% (in man) and 2% (in rat) interact with proteins. The finding that urate is almost completely filtered in the glomerulus is discussed. In body areas exposed to low temperatures protein binding of urate may be of importance. Urate uptake by erythrocytes is characterized by two components: a fast component equilibrating almost immediately at about 7% in man and 17% in rat and a slow component reaching equilibrium after 60 min, at 28% and 36%, respectively. The process is described by a mathematical formula. Lowering of the temperature mainly diminishes uptake by the slow component withQ 10-values ranging between 1.5 and 4.0. In the observed range of concentrations the uptake process does not saturate. The results at lower pH-values suggest that it is unionized uric acid which is transported by the slow component. Application of the data to kidney medulla supports the hypothesis that erythrocytes and, probably, to a lesser extent plasma proteins serve as vehicles for urate reabsorption in the countercurrent system. Such a temporary interaction enables uric acid to escape recirculation and to leave the kidney medulla.
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  • 80
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    Psychopharmacology 39 (1974), S. 237-244 
    ISSN: 1432-2072
    Keywords: Antagonism ; Fixed Interval ; Scopolamine ; Physostigmine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The purpose of this research was to determine if 2 drugs, scopolamine and physostigmine which have opposite effects on cholinergic transmission also produce opposite effects on fixed-interval (FI) performance. Scopolamine and a wide range of doses of physostigmine were administered singly and concurrently to a number of rats responding on a FI 2 min schedule. Scopolamine produced a disruption in FI curvature which could be antagonized by physostigmine, but physostigmine by itself produced no consistent change.
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  • 81
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    Psychopharmacology 40 (1974), S. 91-99 
    ISSN: 1432-2072
    Keywords: Lithium ; Social Behaviour ; Sex ; Novelty ; Photographs ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Effects of lithium chloride on the social behaviour of male and female rats were measured in unfamiliar and familiar test situations using a photographic technique. Lithium-treated females showed an increase in body contact and a decrease in social distances in comparison with saline-treated controls in both test conditions. Males administered lithium showed increased corner occupancies in the novel test setting while in the familiar test they showed decreased body contact and increased average group social distance in comparison with the saline condition. Further tests in an exploration box confirmed that lithium decreased the general environmental responsiveness of male rats. The results are discussed with reference to the anti-aggressive effect of lithium.
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  • 82
    ISSN: 1432-0878
    Keywords: LRF ; Hypothalamic localization ; Rat ; Ependyma ; Glia ; Light and electron microscopic Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Light and electron microscopic autoradiographic analysis of the medial basal hypothalamus of rat brains incubated for 30 and 60 minutes in tritiated luteinizing releasing factor (3H-LRF) revealed selective uptake in the form of silver grains over specialized ependyma (tanycytes) and perivascular glial cells in the palisade-contact zone of the median eminence. The functional capacity of tanycytes and glia are discussed in light of these data.
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  • 83
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    Cell & tissue research 150 (1974), S. 493-496 
    ISSN: 1432-0878
    Keywords: Serotonin ; Neurotransmitter ; Myenteric plexus ; Rat ; Histofluorescence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Several recent studies suggested that serotonergic neuron-like elements are present in the guinea pig ileum. The present paper reports an extensive study of the digestive tract of the rat with the use of a histofluorescence technique. Administration of the serotonin precursor, tryptophan, associated with a monoamine oxidase inhibitor, did not allow histochemical demonstration of rapidly fading, yellow fluorescent, 6-hydroxydopamine-resistant neurons; conversely such neurons were readily detected in the brain. It is concluded that serotonergic neuron-like elements cannot be detected histochemically in the rat myenteric plexus area after chemical sympathectomy.
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  • 84
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    Cell & tissue research 151 (1974), S. 457-469 
    ISSN: 1432-0878
    Keywords: Juxtaglomerular apparatus ; Rat ; Adrenalectomy ; Renin and secretory granules ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Reaktion des juxtaglomerulären Apparates auf Adrenalektomie wurde untersucht. Im Stadium der Nebenniereninsuffizienz, sechs Tage nach der Operation, wurde quantitativ morphometrisch eine Abnahme der Volumendichte der Sekretgranula (von 32% auf 16%) festgestellt. Golgi-Apparat und Ergastoplasma proliferieren stark, wobei insbesondere die erweiterten Cisternen des Ergastoplasmas auffallen.
    Notes: Summary The response of the Juxtaglomerular apparatus to bilateral adrenalectomy was studied in rats. After the sixth postoperative day, symptoms of severe adrenal insufficiency had developed. In the Juxtaglomerular cells, the volume density of the secretory granules decreased from 32% to 16%. The Golgi apparatus and rough endoplasmic reticulum underwent considerable proliferation, the latter showing strikingly enlarged cisternae.
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    Cell & tissue research 151 (1974), S. 525-536 
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Rat ; Sex differences ; Gonadal hormones ; Karyometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Adrenal glands of adult female rats are heavier than the glands of corresponding male rats. Postpubertal orchiectomy increases the adrenal weight, an effect restored by testosterone replacement. Under the same conditions ovariectomy of 8 weeks duration does not change the adrenal weight while estradiol replacement enhances the relative adrenal weight. Karyometric studies have shown that nuclei in the female zona fasciculata cells are larger (app. 18%) than those of the male. Similar but only slight differences (2%) were observed in the zona reticularis. Orchiectomy results in enlargement of cell nuclei within all zones of the adrenal cortex; testosterone replacement has the opposite effect. Ovariectomy of 8 weeks duration slightly enhances the volume of nuclei of the zona glomerulosa cells, has no effect on the nuclei of the zona fasciculata and reduces the volume of nuclei in the zona reticularis. Estradiol replacement reduces the volume of nuclei of the zona glomerulosa cells but increases nuclear volume in the zona fasciculata and in the zona reticularis. Thus testosterone has an inhibitory effect on the adrenal cortex of the rat while the physiologic effect of estradiol on the morphology of this gland, particularly on the zona fasciculata cells is rather dubious. The author wishes to thank Mrs. B. Westerska and Miss K. Siejak for excellent technical assistance.
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    Cell & tissue research 151 (1974), S. 537-547 
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Rat ; Sex differences ; Gonadal hormone ; Stereologic studies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Adult female rats have heavier adrenals than males. Orchiectomy increases the adrenal weight, an effect reversed by testosterone. Neither ovariectomy nor estradiol replacement has an effect on absolute adrenal weight. The stereologic analysis of the volume fractions of particular adrenocortical zones have shown that the volume fraction of the zona glomerulosa in females is smaller as compared with males. On the contrary, the volume fractions of the fasciculata and reticularis zones are higher in female than in male rats. In both sexes gonadectomy and gonadal hormone replacement has an effect on the volume fractions of particular adrenocortical zones, these changes being more pronounced due to orchiectomy or testosterone replacement. The adrenal cortex of all experimental groups contains a similar quantity of parenchymal cells. The cytoplasm volume of a single adrenocortical cell is higher in all zones of the female adrenals as compared with the male. Orchiectomy increases the volume of the cytoplasm in fasciculata and reticularis cells. This effect was reversed by testosterone. Neither ovariectomy nor estradiol replacement has an effect on the volume of the cytoplasm in the fasciculata and reticularis cells. These studies have shown that sex differences with regards to rat adrenal size and weight depend upon the “physiologic atrophy” of the male adrenal cortex, while neither ovariectomy (8 weeks after operation) nor estradiol replacement has a conspicuous effect on the morphologic changes of this gland.
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  • 87
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    Cell & tissue research 147 (1974), S. 259-269 
    ISSN: 1432-0878
    Keywords: Nerve endings ; Hair ; Rat ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Palisade-shaped nerve endings of the small normal hairs of the rat snout were examined with the electron microscope (fixation by perfusion). The terminals are located inside the ‘glassy membrane’ in the area of the neck of the hair root. The 10–20 radially arranged terminal axons are in direct contact with the basement membrane of the epithelium of the external root sheath. The axons are surrounded on all sides by leaf-shaped processes of the Schwann cells. The surfaces of these cell processes are marked by numerous vesicle-like invaginations (approx. 1000 Å dia.). Transverse sections from several areas of the palisadeshaped nerve endings are compared with longitudinal sections. In the upper area ‘empty’ vesicles (approx. 500–600 Å in diameter) occur, along with electron-dense vesicles (approx. 800–1100 Å in diameter); in the middle area, the axons are distended and contain accumulations of mitochondria.
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  • 88
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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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  • 89
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    Cell & tissue research 148 (1974), S. 57-67 
    ISSN: 1432-0878
    Keywords: Prostate ; Rat ; Cyproterone ; Alterations ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The dorsal lobe and the coagulating gland of the rat prostate were studied after administration of the anti-androgenic compound Cyp A for varying periods (7–20 days). There was a general involution of the organs with macroscopic atrophy and reduced amount of secretory material. Ultrastructurally the cells were pale, contained less organelles as compared with the controls, loss of cytoplasm and reduction both of cell height and width. The major changes also included reduction of the Golgi area, the rough endoplasmic reticulum and the number of free ribosomes. Within the dorsal lobe prominent nuclear changes were found, comprising different types of intranuclear inclusions of membranous configurations. The alterations observed in the present study are similar to the changes which were found in castrated animals and are consistent with atrophy. The results are discussed in relation to the available biochemical and autoradiographic data on the different lobes.
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    Cell & tissue research 150 (1974), S. 95-105 
    ISSN: 1432-0878
    Keywords: Mucosal mast cells ; Rat ; Compound 48/80 ; Degranulation, Release ; Light microscopy ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Mast cells in the tongue and lamina propria of the duodenal mucosa, representing two cell types with different morphological, histochemical and functional properties have been studied under the electron microscope. Both cell types were found to contain similar moderately electron dense and homogeneous granules surrounded by a tight membrane constituting the basic ultrastructural characteristics of mast cells. The mucosal mast cells, however, contained fewer granules per cell and the individual granules often exhibited considerable variation in size. In addition the mucosal mast cells, unlike those of the tongue, peritoneum and skin, had a smooth plasma membrane lacking microvilli and possessed irregularly shaped or lobulated nuclei. In the tongue mast cells, administration of Compound 48/80 caused the formation of vacuoles around the granules, expulsion of granules from the cells and disintegration of the granular matrix, but no changes that could be attributed to 48/80 could be found in the mucosal mast cells.
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  • 91
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    Cell & tissue research 150 (1974), S. 167-178 
    ISSN: 1432-0878
    Keywords: Pigment cell ; Red hair ; Sunburn ; Man ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pigment cells of human red hair (pheomelanocytes) are never connected to keratinocytes by desmosomes or other defined cell junctions. In the dendritic processes of pheomelanocytes, thin filaments, about 50–80 Å in diameter, and microtubuli can be observed. Early prepheomelanosomes contain loosely arranged filaments. With the onset of pheomelanogenesis dense material is deposited on the filaments. Distinction between late prepheomelanosomes and pheomelanosomes is not clearly possible, because of the disorganized appearance of the content. Furthermore, the content of pheomelanosomes sometimes seems to be disintegrated. By means of the DOPA reaction, tyrosinase activity is shown to be present in: a) prepheomelanosomes, b) large cisternae apposed at one side of dictyosomes, c) small cisternae of the smooth endoplasmic reticulum, and d) coated and uncoated vesicles. The results suggest that red pigment granules are formed in a manner similar to that of melanin granules. It is further assumed that an inadequate stability of pheomelanoprotein accounts for the inability of red-haired people to develop effective protection against ultraviolet light.
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    Cell & tissue research 154 (1974), S. 443-470 
    ISSN: 1432-0878
    Keywords: Oocytes and T-prospermatogonia ; Rat ; Quantitative analysis ; Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Bei der Ratte findet die sexuelle Differenzierung der Gonade zwischen dem 14. und 15. Tag post conceptionem (p.c.) statt. Während dieser Zeit teilen sich die Oogonien und deren Parallelpopulation—die M-prospermatogonien (multiplying prospermatogonia) oder I-Gonocyten—sehr häufig. Um den 17. Tag p.c. tritt die letzte Generation der Oogonien bzw. der M-prospermatogonien in die Mitose. Die Mitosen bilden häufig “synchronisierte Gruppen”. Die postmitotischen Kerne ihrer Tochterzellen—der Oocyten und der T 1 prospermatogonien (primary transitional prospermatogonia) oder II-Gonocyten—sind klein. Ihr Chromatin ist in Form gröberer Schollen der Kernmembran angelagert. Auf diese Weise kommt das typische “krustenförmige” Aussehen bzw. die Ähnlichkeit mit den Prophasen der Oogonien und M-prospermatogonien zustande. Die Oocyten durchlaufen zunächst die G1-phase (etwa 10 Std Dauer) und treten dann—am Ende des Präleptotänstadiums—in die S-phase. Dann passieren sie die verschiedenen Stadien der meiotischen Prophase und treten vom 3. Tag post partum (p.p.) ab in das Dictyotänstadium. Die T1-prospermatogonien hingegen befinden sich etwa 10 Tage lang in der G1-phase, ohne wesentliche morphologische Veränderungen aufzuweisen. Vom 4. Tag p.p. an durchlaufen sie die S-Phase. Die S-Phasen-Dauer (D-S) beider Zellarten beträgt 11.5 Std und wurde durch Doppelmarkierung mit 14C- und 3H-Thymidin bestimmt. Als am besten geeignete Termine für die Bestimmung der D-S erwiesen sich bei den Oocyten der 18. Tag p.c. und bei den T1-prospermatogonien der 5. Tag p.p. Zu diesen beiden Zeitpunkten war die Anzahl der in die S-phase ein-und austretenden Oocyten bzw. T1-prospermatogonien gleich, die Zellen in S-phase befanden sich im “steady state”. Das Kernvolumen der Oogonien und M-prospermatogonien ist etwa doppelt so groß wie das der postmitotischen Oocyten und T1-prospermatogonien. Bis zum 5. Tage p.p. nimmt das Kernvolumen der Oocyten und T1-prospermatogonien um etwa das Fünffache zu. Der Degenerationsindex der Oocyten liegt wesentlich höher als der der T1-prospermatogonien; er ist postnatal besonders hoch. Aus den T1-prospermatogonien gehen am 4. und 5. Tage p.p. durch Teilung die T 2-prospermatogonien (secondary transitional prospermatogonia) hervor. Die Kerne dieses Zelltyps sind etwas kleiner also die der T1-prospermatogonien. Die T2-prospermatogonien treten am 6. Tage p.p. in die Mitose; es entstehen die ersten A-spermatogonien.
    Notes: Summary In the rat (Wistar-WU) sexual differentiation of the gonads occurs between days 14 and 15 post conception (p.c.). At this time the oogonia and their parallel population — the M-prospermatogonia (I-gonocytes)—divide rapidly. On about day 17 p.c., the last generation of oogonia and M-prospermatogonia, frequently arranged in synchronized clusters, enters mitosis. The postmitotic nuclei of their daughter cells—oocytes and T 1-prospermatogonia (II-gonocytes)—are small; coarse flakes of chromatin are associated with the nuclear membrane causing the typical “crustlike” appearance and the similarity with the prophases of oogonia and M-prospermatogonia. After the oocytes have passed a G1-phase of approximately 10 hr, they enter the S-phase at the end of the preleptotene stage. Then they pass the different stages of the meiotic prophase until they enter the dictyate stage from 3 day post partum (p.p.) onwards. The T1-prospermatogonia, on the other hand, spend a long G1-phase of about 10 days without any conspicuous morphological change before entering the S-phase from day 4 p.p. onwards. The duration of the S-pbase (D-S) of both cell types—oocytes and T1-prospermatogonia—as determined by the double labeling method with 14C- and 3H-thymidine is found to be 11.5 hr. The most favourable time for determining the D-S was day 18 p.c. for the oocytes and day 5 p.p. for the T1-prospermatogonia. On these two days the balance was reached between the cells entering and leaving the S-phase. The nuclear volumes of the postmitotic oocytes and T1-prospermatogonia are approximately half the size of those of their precursors. Until day 5 p.p. the nuclear volumes of the oocytes and T1-prospermatogonia increase about fivefold. The degeneration index of the oocytes is considerably higher than that of the T1-prospermatogonia; postnatally it is especially high. T 2 prospermatogonia arise by mitosis of the T1-prospermatogonia on day 4 and 5 p.p. The nuclei of this cell type are smaller than those of T1-prospermatogonia. T2-prospermatogonia enter mitosis on day 6 p.p and give rise to A-spermatogonia.
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    Cell & tissue research 155 (1974), S. 231-243 
    ISSN: 1432-0878
    Keywords: Pinealocyte-resembling cells ; Habenular region ; Sympathetic nerve fibres ; Ontogenetic development ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The cells of the pineal gland, the pineal stalk, and the lamina intercalaris contain 5-HT and are innervated by sympathetic nerve fibres. These peripheral nerve fibres continue rostrally from the lamina intercalaris and run into the central nervous tissue of stria medullaris and the habenular nuclei. Pharmacological treatment to increase the cellular 5-HT content revealed that the sympathetic fibres are in close relation to yellow fluorescent cells embedded in the brain tissue. These yellow fluorescent cells develop very late in the ontogenetic development (three weeks or more postnatally) and are preceded by ingrowth of sympathetic fibres into the brain tissue. The results support the hypothesis that the cells found in the habenular region are of pinealocyte rather than neuronal nature, but it is possible that they differ in certain aspects from the cells of the pineal gland proper.
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    Cell & tissue research 148 (1974), S. 203-211 
    ISSN: 1432-0878
    Keywords: Hypothalamus ; Rat ; Supraoptic nucleus ; Ultrastructure ; Somatic spines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron microscopic studies of ultrathin serial sections of the perikarya and adjacent neuropil of neurons of the supraoptic nucleus (SON) of the adult male rat revealed varying forms of two types of somatic spines. One type forms synapses with axons passing the cell, the other, without synapses, appears to serve as a buttress or clasp for adjacent neuronal and glial processes. The synapse-bearing spines lack the usual spine apparatus but contain the flocculent substance often seen in spines. The other spines do not exhibit either of these structures. These somatic spines were also seen in Golgi impregnated preparations but the types could not be distinguished. Certain axons synapse either on a somatic spine of the perikarya or penetrate the glial sheath of the neuron and synapse, usually repeatedly, on the soma in an en passant manner.
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  • 95
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 148 (1974), S. 371-379 
    ISSN: 1432-0878
    Keywords: Pineal gland ; Rat ; Electric coupling areas ; Freeze-etching
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The pineal glands of Wistar rats were fixed in glutaraldehyde and prepared by the freeze-etching technique. With regard to the form and internal structure of pineal cells this technique has revealed nothing essentially new. Synaptic ribbons are very rarely found. A regular diagonal arrangement of membrane attached particles between the Schwann cell and the axon of an autonomic nerve terminal was observed. Three types of contact areas between pineal cells are described. In the first two types, which occur more frequently, the diameter of the area varied from 1000 to 2500 Å, with irregularly aggregated membrane associated particles. The third type, larger but less frequently found, has a surface area of 0.4 μm2 and much more regularly distributed membrane associated particles (ø 88 Å). These contact areas can be considered to be electric coupling areas between pineal cells.
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  • 96
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    Electronic Resource
    Springer
    Cell & tissue research 147 (1974), S. 285-292 
    ISSN: 1432-0878
    Keywords: Median eminence ; Rat ; Serotonin terminals ; 5,6- and 5,7-Dihydroxytryptamine ; Chemical degeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Electron microscopical evidence for the existence of an important serotonergic input to the rat median eminence is presented. This evidence is based on the demonstration of degenerating nerve terminals in the external layer of the rat median eminence following the application of 5,6-dihydroxytryptamine or 5,7-dihydroxytryptamine, drugs known to exert more or less selective toxic effects on central serotonin neurons. The finding of a serotonergic innervation of the median eminence in mammals has important implications for 5-hydroxytryptamine as a modulator of synthesis and/or release of hypothalamic, hypophysiotropic hormones.
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  • 97
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 149 (1974), S. 91-104 
    ISSN: 1432-0878
    Keywords: Anococcygeal muscle ; Smooth muscle ; Rat ; Innervation, adrenergic
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The rat anococcygeus muscle, which is known from previous functional and histochemical investigations to be a smooth muscle with a dense adrenergic innervation, was studied by electron microscopic methods. The muscle was found to be organized in small bundles of 2 to 8 muscle cells, which were interconnected by desmosome-like junctions and by gap junctions. Small Schwann cell-axon complexes with 1 to 5 axons appeared to represent the functional terminal nerve pathway. Such axon complexes were located at the periphery of the small smooth muscle bundles, they never penetrated into them. A ratio of approximately 6 small axon complexes per 100 muscle cells was found. After glutaraldehyde fixation axon varicosities contained mainly small empty vesicles. After treatment with 5-hydroxydopamine and permanganate fixation mainly small vesicles with a dense core were found. The neuromuscular distances ranged from 550 to 5000 Å, with a mean of about 2600 Å. True close neuromuscular contacts at a distance below 500 Å with a fusing of basal laminae were absent. The present observations provide a morphological base for the findings of previous electrophysiological and pharmacological studies on the anococcygeal muscle.
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  • 98
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    Springer
    Cell & tissue research 149 (1974), S. 113-120 
    ISSN: 1432-0878
    Keywords: Adrenal cortex ; Rat ; Sex-hormones ; Ultramorphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Ultramorphometrisch wurde nach dem Verfahren von Rohr et al. (1971) die äußere Zona fasciculata von Sprague-Dawley-Ratten bei 5 Gruppen zu je 4 Tieren verglichen: Männchen, Weibchen im Diöstrus, Weibchen im Östrus, männliche und weibliche Kastraten (Kastration am 4. Lebenstag). Die Nebennierenrindenzellen der äu\eren Fasciculata sind bei Weibchen gegenüber denen normaler Männchen hypertroph: Weibchen im Diöstrus zeigen gegenüber Männchen größere Einzelzellen mit vermehrtem glattem endoplasmatischem Reticulum, erhöhten Einzel- und Gesamtvolumina der Mitochondrien sowie einem höheren Lipoidgehalt bei stärkerer Dispersion der Liposomen. Dieselben funktionsspezifischen Strukturen nehmen bei den Weibchen im Östrus noch weiter zu. Die Kastration der Weibchen am 4. Lebenstag führt zu einer Reduktion der funktionsspezifischen morphometrischen Parameter unter die Werte der Diöstrus-Tiere. Männliche Kastraten gleichen die Werte ihrer funktionsspezifischen Strukturen weitgehend denen der Weibchen im Diöstrus an. Nach Kastration am 4. Lebenstag zeigen weibliche Tiere somit etwas niedrigere morphonietrische Parameter in der äußeren Zona fasciculata als die männlichen Kastraten.
    Notes: Summary With the method of Rohr et al. (1971) the outer zona fasciculata of Sprague-Dawley-rats was compared ultramorphometrically in 5 groups of 4 animals each: males, females during diestrus, females during estrus, male and female castrates (castration on 4th day of life). Adrenal cortical cells of the outer fasciculata in females are hypertrophic in comparison with those of normal males: females during diestrus show in comparison with males larger individual cells with increased SER, increased volume of the individual mitochondrium and total volume of mitochondria as well as an increased lipoid content together with a more pronounced dispersion of liposomes. The same function-specific structures show a further increase in females during estrus. Castration of females on the 4th day of life leads to a reduction of the function-specific morphometric parameters below the values of the diestrus animals. Male castrates show adaption of the values of their function-specific structures towards those of females during diestrus. Following castration on the 4th day of life, female animals thus show somewhat lower morphometric parameters in the outer zona fasciculata than male castrates.
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  • 99
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    Electronic Resource
    Springer
    Cell & tissue research 149 (1974), S. 235-243 
    ISSN: 1432-0878
    Keywords: Adrenal zona glomerulosa ; Rat ; Normal ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary This paper reports on an electron microscopic study of the adrenal zona glomerulosa in the normal rat, with special emphasis on the structural diversity of mitochondria in its parenchymatous cells. The mitochondria of cristae may be tubulo-vesicular, plate-like and/or straight tubular, any one mitochondrion containing one or more types of cristae. The mitochondrial features of the zona glomerulosa parenchymatous cells are attributed to the biochemical stages of aldosterone synthesis, taking place in different mitochondria of these cells.
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  • 100
    ISSN: 1432-0878
    Keywords: Hypothalamo-neurohypophysial system ; Rat ; Granule distribution ; Electron microscopy, morphometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Neurohypophyse und die neurosekretorischen hypothalamischen Kerngebiete von normalen männlichen und weiblichen Ratten, von trächtigen und durstenden Tieren wurden elektronenmikroskopisch und morphometrisch mit der Fragestellung untersucht, ob sich in den Häufigkeitsverteilungen der mittleren Granula-Durchmesser, bezogen auf die Anzahl der Axone, eine zweigipflige Verteilung ergibt. Bei Kontrolltieren zeigen die Perikarya des Nucleus supraopticus zahlreichere und größere Granula als die Zellen des Nucleus paraventricularis, wobei der Unterschied in den Durchmessern der Granula bei den weiblichen Tieren ausgeprägter ist als bei den männlichen. Beide Kontrollgruppen zeigen in der Neurohypophyse ein zweigipfliges Verteilungsmuster der Granula, wobei die beiden Gipfel bei den männlichen Kontrollen dichter beieinander liegen als bei den weiblichen. Bei den trächtigen Tieren weisen beide Kerngebiete Zeichen gesteigerter Aktivität auf und die Granula in den Zellen des Nucleus paraventricularis sind deutlich größer als bei Kontrolltieren. Zu Beginn der Tragzeit werden relativ große, wahrscheinlich vasopressinhaltige Granula in der Neurohypophyse gespeichert, während sich im letzten Drittel der Tragezeit die beiden Populationen dort nicht mehr unterscheiden lassen. Nach 48 Std. Wasserentzug erscheinen beide hypothalamischen Kerne aktiviert. Auffallend ist, daß die Granula im Nucleus supraopticus deutlich kleiner sind als bei Kontrolltieren. Entsprechend fehlen in der Neurohypophyse große Granula, während Axone mit kleinen Granula vermehrt sind. Nach zehntägiger Durstperiode lassen sich im Nucleus supraopticus, neben sehr typischen morphologischen Veränderungen, morphometrisch ebenfalls deutlich kleinere Granula nachweisen. Im Hypophysenhinterlappen dieser Versuchsgruppe sind die granulahaltigen Axone sehr stark vermindert, und in der Häufigkeitsverteilung fehlen die Granula mit großem Durchmesser während der dem Oxytocin zugeordnete Gipfel unverändert erscheint. In Verbindung mit den elektronenmikroskopischen Befunden lassen sich also aus den Verschiebungen der Verteilungsmuster zwischen den sechs Versuchsgruppen die Granula mit kleinerem Durchmesser oxytocinhaltigen Axonen zuordnen und Granula mit größerem Durchmesser zu den Endigungen, die Vasopressin enthalten. Die morphometrischen Befunde in den neurosekretorischen hypothalamischen Kerngebieten bestätigen diese Zuordnung. Die elektronenmikroskopischen und morphometrischen Befunde werden besonders im Hinblick auf die Hormonverschiebungen zwischen dem “reserve pool” und den “easily releasable pool” diskutiert.
    Notes: Summary A morphometric evaluation of electron micrographs has been carried out from neurosecretory terminals in the neurohypophysis and from the supraoptic and paraventricular nuclei in normal male and female rats as well as in pregnant and water deprived rats. The task of this investigation was to find out whether frequency distribution diagrams of the mean diameter of the neurosecretory granules, plotted versus the number of axons, reveal a grossly bimodal distribution. In normal rats the nerve cells of the nucleus supraopticus (S.O.N.) show more numerous and larger granules than the cells of the nucleus paraventricularis (P.V.N), this difference with respect to the diameter being more pronounced in female than in male animals. In the posterior pituitary lobes the neurosecretory granules exhibit a bimodal distribution, the second peak being situated more closely to the first one in male controls. In pregnant animals both nuclei appear to be activated, and the granules of P.V.N. are distinctly larger as compared to those of female control animals. In early pregnancy larger, i.e. presumably vasopressin-containing granules are stored in the neurohypophysis, while in the last phase before delivery oxytocin-containing neurons and vasopressin-containing ones cannot be differentiated any more. After 48 hrs of thirst both hypothalamic nuclei exhibit signs of increased activation, the diameters of the granules in the S.O.N. being distinctly smaller than in normals. In the neurohypophysis granules with large diameters are lacking, while axons with small granules are more frequent. In the S.O.N. of animals, water deprived for 10 days the diameters of the granules are smaller than normal and in the neurohypophysis the number of granule-containing fibres is strongly reduced. In the frequency distribution diagram granules with larger diameters are lacking whereas the peak, attributed to oxytocin, is not essentially altered. However, from the observed alteration on the distribution patterns of the six experimental groups and in connection with the electron microscopic results the granules with smaller diameters can be attributed to oxytocin-containing axons and the larger ones to vasopressin-containing terminals. Analogous morphometric data have been obtained from the neurosecretory nuclei as well. The electron-microscopic and morphometric observations are discussed with regard to hormone-shifts between the reserve pool and the easily-releasable pool.
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