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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    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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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    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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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    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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  • 4
    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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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    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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  • 6
    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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  • 7
    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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  • 8
    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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  • 9
    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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  • 10
    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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  • 11
    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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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    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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  • 13
    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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  • 14
    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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  • 15
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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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  • 16
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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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  • 17
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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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  • 18
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    Langenbeck's archives of surgery 336 (1974), S. 15-23 
    ISSN: 1435-2451
    Keywords: Rat ; Splenectomy ; Gastric Ulceration ; Increase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An Ratten wurde der Einfluß von Splenektomie auf Magensaftsekretion und Ulcusentstehung untersucht. Sowohl nach “restraint-stress” als auch Pylorusligatur wiesen die splenektomierten Tiere eine ausgeprägte Steigerung der Ulcuszahl und -größe gegenüber den Kontrolltieren auf. In der Magensaftanalyse waren dagegen die Werte der splenektomierten Tiere gegenüber den scheinoperierten nur geringgradig gesteigert. — Als mögliche Ursache der vermehrten Ulcusanfälligkeit nach Splenektomie wurde eine Veränderung lokaler, nicht säuresekretorischer Faktoren der Magenwand diskutiert.
    Notes: Summary In Splenectomiced rats incidence of gastric ulceration was compaired with control groups. Restraint stress and ligation of pylorus was used as model. Splenectomiced rats do show an higher incidence in both models. Both frequency and extension of gastric ulcer were accumulated significantly. Analysis of gastric secretion was only unessentially raised in comparisom to control-groups. Change of protective factors of stomach as possible reason is discussed.
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  • 19
    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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  • 20
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    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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  • 21
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    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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  • 22
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    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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  • 23
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    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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  • 24
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    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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  • 25
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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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  • 26
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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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  • 27
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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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  • 28
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    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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  • 29
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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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  • 30
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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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  • 31
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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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  • 32
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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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  • 33
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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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  • 34
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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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  • 35
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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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  • 36
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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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  • 37
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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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  • 38
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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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  • 39
    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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  • 40
    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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  • 41
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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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  • 42
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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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  • 43
    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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  • 44
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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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  • 45
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    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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  • 46
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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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  • 47
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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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  • 48
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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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  • 49
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    Cell & tissue research 151 (1974), S. 471-480 
    ISSN: 1432-0878
    Keywords: Juxtaglomerular apparatus ; Rat ; Influence of deoxycorticosterone (DOC) ; Electron microscopy ; Morphometric analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die quantitativ-morphologische Analyse des juxtaglomerulären Apparates nach DOC-Behandlung zeigte, daß mit der Hemmung der Reninbildung eine Hypoplasie der epitheloiden Zellen des juxtaglomerulären Apparates einhergeht. Der Granulagehalt der juxtaglomerulären Zellen nahm ab; die Kern-Plasma-Relation änderte sich und die Leiomyofibrillen in den Epitheloidzellen nahmen zu. An den übrigen Anteilen des juxtaglomerulären Apparates, insbesondere der Macula densa, wurden keine morphologischen Veränderungen beobachtet. Die DOC-Behandlung führte darüber hinaus zu einer Bildung von Einschlüssen in den Podocyten, den Mesangiumzellen und den Zellen der Bowman-Membran. Die verschiedenen Möglichkeiten, über welche Faktoren die juxtaglomerulären Zellen nach DOC-Behandlung degranuliert werden, werden diskutiert. Das ultrastrukturelle Bild der Epitheloidzellen nach DOC-Behandlung entspricht deutlich einer gehemmten Sekretion, da das Ergastoplasma und der Golgi-Apparat ganz besonders stark zurückgebildet werden.
    Notes: Summary Quantitative morphological analysis of the Juxtaglomerular apparatus of rats treated with deoxycorticosterone (DOC) and salt revealed hypoplasia of the epithelioid cells as a concomitant of the inhibition of renin synthesis. The granular content of the Juxtaglomerular cells was significantly decreased, while the nucleus-to-cytoplasm ratio and the volume density of leiomyofilaments in the epithelioid cells increased. No morphological alterations were observed in the remaining constituents of the Juxtaglomerular apparatus, including the macula densa. DOC-treatment also induced the appearance of inclusions in the podocytes in the cells of the mesangium, and in the cells of Bowman's capsule. The possible mechanisms of degranulation of the Juxtaglomerular cells after treatment with DOC are discussed. The ultrastructural appearance of the epithelioid cells after treatment with DOC corresponds to an inhibition of secretion, since the rough endoplasmic reticulum and the Golgi apparatus undergo marked regressive changes.
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  • 50
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    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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  • 51
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    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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  • 52
    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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  • 53
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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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  • 54
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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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  • 55
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    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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  • 56
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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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  • 57
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    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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  • 58
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    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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  • 59
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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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  • 60
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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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  • 61
    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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  • 62
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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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  • 63
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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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  • 64
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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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    Anatomy and embryology 139 (1973), S. 119-126 
    ISSN: 1432-0568
    Keywords: Cleavage stages ; Egg-cylinder ; Mouse ; Rat ; Hydrolytic enzymes distribution ; Differentiation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The time of appearance and the distribution of alkaline and acid phosphatase and nonspecific esterase was investigated in cleavage and early postimplantation stages of mouse and rat embryos. Alkaline and acid phosphatase appeared for the first time in 8-cell embryos. Activity of both enzymes grew progressively stronger to blastocyst stage. Acid phosphatase activity was revealed in the form of fine and coarse granules distributed evenly in the cytoplasm. Alkaline phosphatase was predominantly localized in plasma membranes. There was no difference in intensity of reaction between trophoblastic cells and the inner cell mass. After implantation acid phosphatase was localized in coarse granules in the apical portion of entodermal cells. With the appearance of mesoderm, the cells of embryonal entoderm became flattened and devoid of acid phosphatase activity which was restricted to cells of extraembryonic entoderm. The activity of nonspecific esterase was not detected in preimplantation stages. In postimplantation embryos it roughly corresponded to the activity of acid phosphatase. Alkaline phosphatase was localized in cell membranes of ectodermal cells. The mesodermal cells of mouse embryo displayed a somewhat weaker activity than ectodermal cells, while in the rat embryo the same layer remained completely nonreactive. Our findings on the distribution of the enzymes mentioned did not reveal any kind of polarity or bilateral symmetry in preimplantation stages. In postimplantation stages acid phosphatase and nonspecific esterase are probably bound to lysosomes and play an important role in embryonic nutrition. The absence of alkaline phosphatase from entodermal cells is somewhat puzzling and suggests that the process of molecular transport in those cells is most probably restricted to endocytosis. Our results suggest that all blastomeres are identical with respect to enzyme distribution and that the first signs of differentiation of enzyme content appear with the formation of germ layers.
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  • 66
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    Anatomy and embryology 141 (1973), S. 125-150 
    ISSN: 1432-0568
    Keywords: Rat ; Columns ; Swirls ; Interneurons ; Projection neurons ; Subdivisions ; Morphology ; Golgi ; Nissl ; Axons ; Dendrites ; Cerebellum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The lateral nucleus in the rat is investigated with several variants of the rapid Golgi method and in Nissl preparations. The neurons are divided into two classes according to their size and the disposition of their axons. The smaller neurons or interneurons have cross sectional areas less than 180 μm2, and short axons that ramify in the vicinity of the cell bodies. Small neurons have also been seen on rare occasions with longer axons that may leave the nucleus. The larger cells (areas greater than 180 μm2) have long axons that leave the nucleus and emit short, beaded, recurrent collaterals. In the rostral and caudal poles of the lateral nucleus, the large projection neurons as well as the small neurons are multipolar with swirled dendritic arborizations. Neurons in the dorsal rim and ventral third of the nucleus have similar dispositions of their dendrites. In the central columnar zone, the projection neurons have dendrites that are arranged in columns directed diagonally across the body of the nucleus in the 4 to 10 o'clock direction in the right lateral nucleus and the 8 to 2 o'clock direction in the left nucleus. A collection of small neurons is generally found in the medial hilus zone. In each part of the lateral nucleus, the neurons are arranged in characteristic ways.
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  • 67
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    Anatomy and embryology 141 (1973), S. 161-169 
    ISSN: 1432-0568
    Keywords: Rat ; Uterus ; Stroma ; Ultrastructure ; Sex steroids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effect of progesterone and oestrogen on the central uterine stroma has been examined in order to analyze what changes occur when the uterus is hormonally prepared for implantation. Both progesterone and oestrogen, when given separately, cause nucleolar enlargement and growth of the granular endoplasmic reticulum. However, after progesterone treatment the nuclei are large and spherical whereas they are spindle-shaped after oestrogen treatment. When oestrogen is administered to the progesterone-treated rat little change occurs in the stromal morphology. There is little morphological support to the view that oestrogen acts on the stroma to increase endometrial sensitivity. Further, progesterone seems to stimulate the synthesis of RNA and of cellular protein only in the stromal cell while oestrogen has a similar effect in all cell types of the uterus.
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  • 68
    ISSN: 1432-0568
    Keywords: Capillaries ; Endothelial cell ; Ontogenesis ; Morphometry ; Cerebral cortex ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Während der postnatalen Entwicklung wurde die Capillarlänge im Einheitsvolumen (CL), die Verzweigungsdichte (N⊥) und die mittlere Länge der Capillarendothelzellen (LE) in der Lamina IV des senso-motorischen Cortex von insgesamt 64 Rattengehirnen bestimmt. Als Capillaren wurden alle Gefäße unter 8 μm Durchmesser akzeptiert. Die CL bestimmten wir in 1–2 μm dicken Epon-Schnitten nach der Methode von Saltikov. Die Verzweigungen wurden durch Tusche-Gelatine-Injektion dargestellt und in Kryostat-Schnitten visuell gezählt. Im Verlauf des postnatalen Capillarwachstums, das die Bildung von Verzweigungen durch Sprossung und die Verlängerung der bestehenden Geäße umfaßt, nimmt die CL von ca. 200 mm auf 1100 mm pro mm3 Gewebe zu. Die Verzweigungszahl im gleichen Volumen steigt von 1200 kurz nach der Geburt auf ein Maximum von 11500 am Tag 20 und fällt dann allmählich auf den adulten Wert von 9500 ab. Am Ende der ersten Woche p.n. bewirkt die intensive Capillarsprossung eine starke Erhöhung der N⊥. Darauf folgt in der zweiten Woche p.n. die schnelle Zunahme der CL. Die Veränderungen der N⊥ laufen parallel mit Veränderungen im oxidativen Metabolismus. Aus dem Verhältnis N⊥ zu CL läßt sich der Vernetzungsgrad der Capillaren, d.h. die Verzweigungszahl pro mm Capillarlänge, berechnen. Dieser erreicht zwischen Tag 10 und 20 p.n. ein Maximum und sinkt danach bis zum erwachsenen Tier wieder beträchtlich ab. 1 Monat p.n. sind das Wachstum und die Reifung der Hirnrinde bei der Ratte weitgehend abgeschlossen. Die Bildung neuer Sprosse hört auf, und das weitere Kapillarwachstum erfolgt weniger durch Zellteilung als vielmehr durch Verlängerung des Endothels. Die Phase der intensiven Capillarsprossung entspricht zeitlich der vulnerablen Periode der Hirnentwicklung (“brain-growth-spurt”, nach Dobbing). Unsere Befunde lassen die Vermutung zu, daß in dieser Periode Störungen der Capillarsprossung indirekt das weitere Hirnwachstum beeinflussen können.
    Notes: Summary The average length of the capillary endothelial cells (L E ), the capillary length (CL) and the number of vascular ramifications (N⊥) per unit volume in layer IV of the sensorymortor cortex from the brains of 64 Sprague Dawley rats were determined during postnatal development. All vessels less than 8 μm in diameter were accepted as capillaries. The CL was calculated according to the method of Saltikov, by counting capillary profiles in 1–2μm Epon sections. The number of ramifications per test volume were counted in 30 μm frozen sections of India-ink injected brains. Capillary growth involves both the formation of ramifications by sprouting, and the elongation of the existing vessels. During the postnatal period CL increases from 200 to 1100 mm per cubic mm tissue, the extent of branching per unit volume rises from 1200 at birth to a peak of 11500 per cubic mm at day 20 after birth, and then declines to 9500 in adults. Intensive capillary sprouting results in a marked increase in N⊥ at the end of the first week, followed by a rapid increase in CL in the second week. The changes in the ramification density run parallel with the changes in aerobic metabolism during postnatal development. The ratio N⊥/CL, i. e. the number of ramifications per mm capillary length, corresponds to the degree of arborization of the capillary net. This value rises to a maximum level between days 10 and 20 after birth and declines until maturity is attained. After 1 month the growth of rat brain is almost accomplished and the cortical structure has attained its adult characteristics. The formation of new ramifications ceases and further capillary growth occurs to a larger extent by elongation of endothelial cells and not by cell division. The phase of extensive capillary sprouting corresponds to the vulnerable period of brain development (called “brain-growth-spurt” by Dobbing). Our findings lead to the assumption that disturbances during the period of capillary proliferation can indirectly influence further brain development
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  • 69
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    Anatomy and embryology 140 (1973), S. 281-318 
    ISSN: 1432-0568
    Keywords: Central monoamine neurons ; Ontogeny ; Rat ; Fluorescence histochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The development of all monoamine-containing neuron systems in the rat brain throughout the last seven days of gestation, i.e. from the 15th day to term, crown rump length (CRL) 16 mm to 42 mm, has been followed using the Falck-Hillarp method for fluorescence histochemistry. Serial sagittal, horizontal and transverse sections through whole brains of fetuses from MAO-inhibited mothers have been carefully analyzed by fluorescence microscopy, and drawings of almost all sections depicting specific fluorescence have been collected from 10 of the 16 analyzed brains. Thus, all the 5-hydroxytryptamine (5-HT), dopamine (DA) and noradrenaline (NA) neuron systems have been mapped, both regarding the cell groups, the formation of axon pathways and the development of terminal plexuses in the whole brain prenatally. Together with a previous report (Olson and Seiger, 1972a) the present data have made it possible to determine the common origin of groups A1–A3, A4–A7, A8–A10, B1–B3 and B4–B9, respectively (nomenclature according to Dahlström and Fuxe, 1964). These findings and an estimation of the number of visible fluorescent cells in all monoamine cell complexes throughout the prenatal period of development have been summarized in a flow-chart. In the full-term fetus all monoamine neurons and their axon pathways, except for the hypothalamic cell groups, are very well developed. Thus, the new neuroanatomical data presented, in all probability hold true also for the adult state. A comprehension of the innervation course of neostriatum by DA nerve terminals from the 14th day of gestation to adult hood is given.
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    Anatomy and embryology 140 (1973), S. 153-171 
    ISSN: 1432-0568
    Keywords: Rat ; Tongue ; Myogenesis ; Neurogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Um die Entwicklung des Bewegungsapparates der Rattenzunge im Verhältnis zu morphogenetischen Vorgängen im Gesichtsbereich, besonders zur Gaumenentwicklung, beurteilen zu können, wurde die Zungenanlage des Rattenembryos ab Tag 13 p.c. bis Tag 6 p.p. lichtmikroskopisch, histochemisch und elektronenmikroskopisch untersucht. In einem Blastem von embryonalen Mesenchymzellen, Capillaren und Neuritenbündeln differenzieren sich ab Tag 15 p.c. Myoblasten, die miteinander zu mehrkernigen Muskelfasern verschmelzen. In deren Cytoplasma bilden sich an Ribosomenketten Myofilamente, die zu Myofibrillen mit Z-Streifen organisiert werden. Ab Tag 19 p.c. ordnet sich die Querstreifung zu Registern, das Transversolongitudinalsystem lagert sich an. Neuritenbündel legen sich quer zur Längsachse an die Muskelfasern an und ab Tag 17 p.c. finden sich myoneuronale Kontakte. Typische motorische Endplatten wurden bis Tag 6 p.p. nicht gefunden. Zum Zeitpunkt des Gaumenschlusses am Tag 17 p.c. sind geordnete Muskelfasersysteme, primitive myoneuronale Kontakte mit Acetylcholinvesikeln und ein typisches Enzymmuster der Acetylcholinesterase ausgebildet. Damit bestehen vor Schluß des harten Gaumens die strukturellen und enzymatischen Voraussetzungen für eine gerichtete Bewegung der Zunge. Die Hypothese, daß motorische Aktivität zum Gaumenschluß notwendig sei, wird mit Beschreibungen embryonaler Bewegungen, mit der Literatur klinisch-pathologischer Befunde der Gaumenspalte und teratologischen Experimenten verglichen. Danach scheint ein direkter kausaler Zusammenhang zwischen Bewegungen im Kopfbereich und Gaumenschluß nicht vorzuliegen.
    Notes: Summary In order to be able to evaluate the development of the motor system of the rat tongue with respect to the morphogenetic processes in the region of the face, especially palate development, we studied the tongue anlage of the rat embryo from day 13 p.c. to day 6 p.p. histochemically and under the light and electron microscope. From day 15 p.c. onwards myoblasts differentiated out of a blastema consisting of embryonic mesenchymal cells, capillaries and neurite bundles. The myoblasts then fused together to form multinuclear muscle fibres. On the ribosome chains in the cytoplasm myofilaments were formed, which were then organized to myofibrils with Z-lines. From day 19 p.c. onwards the cross-striations came to lie next to each other and the transversolongitudinal system was added. Neurite bundles were added at right angles to the longitudinal axis of the muscle fibres, and from day 17 p.c. myoneural contacts were found. No typical motor endplates were found up to day 6 p.p. At the time of palate closure on day 17 p.c. regular muscle-fibre systems, primitive myoneural contacts with acetylcholine vesicles and a typical acetylcholine-esterase enzyme pattern had been developed. Therefore before closure of the hard palate the structural and enzymatic preconditions existed for a coordinated movement of the tongue. The hypothesis that motor activity is necessary for palate closure is compared with descriptions of embryonic movements, with clinical-pathological results in papers on the cleft palate and with teratogenic experiments. In this respect there does not seem to be any direct causal connection between movements in the head region and palate closure.
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    Anatomy and embryology 141 (1973), S. 3-37 
    ISSN: 1432-0568
    Keywords: CNS ; Cortical plate ; Neuroblasts ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In the cortical plate of the late prenatal rat fetus the neuroblasts can be considered to be of three types: mature neuroblasts which are prominent in the lower levels of the cortical plate and have some of the cytoplasmic and nuclear features of neurons, immature neuroblasts that have recently completed their migrations into the cortical plate, and migrating neuroblasts that are still in the process of moving to their definitive positions. Both of these latter types have darker cytoplasm than the mature neuroblasts. All of the neuroblasts have an apical process that extends directly towards the pial surface of the cortical plate and a basal process that is directed towards the intermediate zone of the developing hemisphere. In Golgi preparations some of these basal processes, particularly those of neuroblasts situated in the lower levels of the cortical plate, seem to have formed axons that pass through the intermediate zone to enter the developing white matter, in which they turn at right angles away from, and rarely toward, the midline. Other elements traversing the cortical plate are the ascending processes of spongioblasts that branch in the molecular layer and form expansions at the surface of the hemisphere. In the molecular layer the spongioblast terminal branches intertwine with the apical tufts of the ascending neuroblast processes and with thin processes that have the features of axons, to form a loose neuropil. In the cortical plate the spongioblast processes are usually closely and preferentially surrounded by the dark migrating neuroblasts and by the immature neuroblasts. Both of these latter may partially encompass spongioblast processes. Hence it is concluded that the spongioblast processes act as guides along which the migrating neuroblasts ascend through the cortical plate.
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  • 72
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    Anatomy and embryology 141 (1973), S. 275-288 
    ISSN: 1432-0568
    Keywords: Cerebral ventricles ; Perinatal period ; Subependymal cells ; Rat ; Light and electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Gehirne von 93 Ratten (letzte Embryonalwoche bis zum 30. postnatalen Tag) wurden licht- und elektronenmikroskopisch untersucht. Am Ende der zweiten Embryonalwoche treten im mittleren Teil des III. Ventrikels Zellen auf, deren Cytoplasma sich mit einer Perjodsäure-Bisulfit-Aldehydthionin-Methode blau anfärben läßt. Die blauen Zellen werden nach der Geburt auch an anderen Abschnitten des III. Ventrikels sowie am Aquaedukt und IV. Ventrikel ausschließlich in einer lockeren subependymalen Gliazone gefunden. Zwischen dem 14. und 17. Tag nimmt ihre Zahl ab, um den 22. postnatalen Tag sind die blauen Zellen völlig verschwunden. Gleichzeitig wird die subependymale Auflockerungszone dichter. Elektronenmikroskopisch werden die blauen Zellen als fortsatzreiche Elemente identifiziert, die viele Mitochondrien und unterschiedlich große Vacuolen und Cytosomen enthalten. Die Fortsätze umschließen subependymale Räume, die ein feinflockiges Material enthalten. Die Zellen werden als mikrogliäre Elemente angesehen, ihre Funktion mit dem Verschwinden der subependymalen Auflockerungszone in Verbindung gebracht.
    Notes: Summary The brains of 93 rats (of between the last week of pregnancy up to the 30th postnatal day) were investigated by means of light and electron microscopy. At the end of the second week of pregnancy, subependymal cells, the cytoplasm of which is blue after staining with a periodic-acid-bisulfit-aldehydethionine-method, begin to appear in the middle part of the IIIrd ventricle. After birth, the blue cells can also be demonstrated in other parts of the IIIrd ventricle as well as in the wall of aquaeduct and the IVth ventricle. The cells are exclusively found in a loosely textured subependymal tissue. Between the 14th and the 17th day the number of the blue cells decreases and around the 22nd postnatal day they disappear completely. Simultaneously, the texture of the subependymal tissue becomes more compact. The blue cells can be identified by electron microscopy. They are characterized by the presence of several processes and contain many mitochondria, different sized vacuoles and cytosomes. The cell processes enclose subependymal cavities containing a loose flocculose material. The cells are considered as microglia cells. Their function is considered in relation to the disappearance of the loose texture of the subependymal zone.
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  • 73
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    Anatomy and embryology 141 (1973), S. 289-317 
    ISSN: 1432-0568
    Keywords: Cerebellum ; Synapses ; Rat ; Interneuron ; Axons ; Perikarya ; Neuroglia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Profiles of large neurons in the lateral nucleus range from 16 μm to 35 μm in diameter with dimpled nuclei, large Nissl bodies, and well developed Golgi apparatus. Two types of perikarya are distinguished, those that are smooth and those with irregular somatic and dendritic protuberances. About 86% of all large neuronal somata are covered with axosomatic synapses, predominantly with terminals of Purkinje axons and a few belonging to axons of the small neurons. The remaining 14% have no axosomatic synapses. The thick, fleshy dendrites of these cells are covered with terminals, the majority of which synapse directly upon the dendritic shaft. A few are present on spines. The initial segment of the large neuron is thick and robust and receives synapses upon its shaft or upon a spinous projection. The small neurons measure less than 12 μm in diameter and have very lobulated nuclei in a sparse cytoplasm characterized by small Nissl bodies and a poorly elaborated Golgi apparatus. About 52% of all small neuronal somata bear no synapses whereas the remaining 48% are covered with axosomatic synapses, mainly from the axons of Purkinje cells and a few axons of other small cells. The slender long dendrites of both large and small cells bear synapses with six classes of axons in the neuropil. Synaptic protuberances of two varieties occur on the surfaces of both perikarya and dendrites, (a) dome-shaped ones capped with a pronounced asymmetrical synaptic junction and (b) ones with thin long necks and bulbous heads having synapses on both parts. Frond-like dendritic excrescences are borne on the processes of some small and large neurons and they are postsynaptic to many axon terminals clustered around them.
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  • 74
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    Anatomy and embryology 142 (1973), S. 103-115 
    ISSN: 1432-0568
    Keywords: Dentinogenesis ; Dentinal globules ; Alkaline phosphatase ; Calcification ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary At the submicroscopic level, extracellular globular membrane-delimited structures have been observed in the matrix in early dentin formation in the rat. Within these “dentinal globules”, needle-like crystallites are found before apatite crystals appear in the filamentous-amorphous ground substance. In sections incubated for alkaline phosphatase, reaction products are closely associated with these globules. The possible role of the globules in initial dentin formation is discussed.
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  • 75
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    Acta neuropathologica 24 (1973), S. 287-303 
    ISSN: 1432-0533
    Keywords: S-100 Protein ; Experimental Neurogenic Tumors ; Nitrosourea ; Rat ; Complement Fixation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary S-100 protein, a soluble protein restricted to the nervous system, was measured by complement fixation in 51 neurogenic and non-neurogenic tumors produced by either methylnitrosourea or ethylnitrosourea in three different strains of rats. Nineteen of the 51 neurogenic tumors were neoplasms of the central nervous system (18 of the brain, 1 of the spinal cord). They were diagnosed morphologically as 5 mixed gliomas, 4 anaplastic gliomas, 4 glioependymomas, 1 ependymoma, 3 gliosarcomas, and 2 unclassified tumors. With the exception of one anaplastic glioma and one gliosarcoma, all other central nervous system tumors contained S-100 protein, ranging from 0.005–0.13% of the total 35000 g supernatant protein. S-100 protein was also demonstrated in 21 of the 22 tumors of the peripheral nervous system, originating from the trigeminal nerves, the spinal roots, and from peripheral nerves. The average S-100 protein content of these tumors was 0.2% (range 0.02–1.6%). A possible correlation between S-100 protein content and tumor differentiation must be evaluated. S-100 protein was detected in only one of 10 neoplasms morphologically classified as non-neurogenic (7 sarcomas, 2 carcinomas, and 1 hemangioendothelioma). On the basis of its S-100 protein content, one tumor was reclassified as a neurosarcoma. The sensitivity and the high degree of specificity of the S-100 protein assay makes it a useful biochemical tool for the identification of neurogenic tumors. The presence of S-100 protein must be considered as a definitive indication for neural cell participation in neoplastic growth.
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  • 76
    ISSN: 1432-0533
    Keywords: Neuronal Inclusions ; Cerebrum ; Cholesterol Inhibitor ; Rat ; Electron Microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Intraperitoneal injections of a hypocholesterolemic drug, AY9944 produced neuronal cytoplasmic inclusions in the brain of Wistar strain of rats. The inclusions were numerous and larger in size in the younger age groups but gradually decreased in number and size after 30 days of age. Only a few small inclusions were seen in rats of 35 days of age or older, in spite of continuous injection of the drug. Inclusions gradually decreased in number after discontinuation of the drug in a relatively younger age group. Injection of the drug in adult rats produced only a few small neuronal inclusions. Ultrastructurally, concentrical lamellar structures were the predominant ones in younger age groups but other types of inclusions were seen in older animals and those receiving lesser amounts of the drug or those which were examined after discontinuation of the drug. This observation suggests that morphologically different inclusions can be formed by basically the same treatment if there is any difference in the metabolic activity of the target cell or the amounts of the drug. Biochemical analysis of the sterols revealed a consistently high level of 7-dehydrocholesterol up to 69 days of age, when AY9944 was administered continuously, despite the fact that there was a decrease in the number and size of the abnormal neuronal inclusions.
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    Experimental brain research 16 (1973), S. 255-275 
    ISSN: 1432-1106
    Keywords: Rat ; Lateral vestibular nucleus ; Giant cells ; Gap junctions ; Electrotonic coupling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Correlation of morphological and electrophysiological data strongly suggest that in rat, the giant cells of the lateral vestibular nucleus (L.V.N.) are electrotonically coupled. 1. in addition to “active zones” large terminals synapsing on the perikaryon and/or the main dendritic trunk of the cells bear “gap” junctions which are interpreted as low electrical resistance pathways between neurons. 2. electrical activity of the giant cells was recorded intracellularly as the vestibulo-spinal tract was stimulated. Graded antidromic stimulation produced graded antidromic depolarizations (G.A.Ds) in 69% of cells with high threshold axons. 3. the latency of the G.A.Ds was too short to allow for chemical transmission through afferents or recurrent collaterals. 4. collision experiments demonstrated that directly evoked spikes blocked the antidromic spikes but did not block the G.A.Ds which thus were accounted for by activation of cells others than the impaled ones. 5. lesion experiments indicated that afferent fibers from the spinal cord terminate exclusively in the dorsal part of the L.V.N. Since G.A.Ds were recorded all throughout the nucleus, they were not excitatory post synaptic potentials (EPSPs) from spinal afferents. 6. when the strength of the spinal cord stimulation was increased EPSPs were also generated but they were distinct from the G.A.Ds by their latencies, time course and maximum amplitude. 7. since no direct contact is observed between neurons it is inferred that, as in other documented cases, coupling between giant cells is mediated by way of presynaptic fibers.
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    Experimental brain research 17 (1973), S. 242-260 
    ISSN: 1432-1106
    Keywords: Past and slow principal cells ; Recurrent inhibition ; Lateral geniculate body ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In urethane-anesthetized albino rats studies were made on mass potentials and/or unit activities of the lateral geniculate body (LGB) in response to single shock stimulation of optic tract (OT) and visual cortex (VC). The previous finding that LGB mass responses to stimulation of the optic nerve comprise at least two postsynaptic waves (r1 and r2) with different peak times was confirmed by OT stimulation. It was found that the r1 wave had a lower threshold and a more rapid recovery process than the r2 wave. Unit responses of principal (P) cells to maximal OT stimulation consisted of short-latency, single spikes (initial spike, IS), followed by long-latency, grouped discharges (late discharge, LD) repeated more than twice (LD1, LDr2 and so forth). Spontaneous discharges were almost completely suppressed after IS and each LD, suggesting that following these evoked discharges P cells underwent a phase of depressed excitability. The latency histogram of IS based upon 212 P cells had two peaks well-corresponding in time to the peaks of the r1 and r2 waves of the mass response, respectively. P cells were divided into the fast and slow groups according to whether their ISs occurred earlier or later than the trough separating the r1 and r2 waves. Typically, the fast cells had lower thresholds than the slow cells. The duration of the post-excitatory depression following IS and LD1 were shorter in the fast cells than in the slow cells. This same was found true with regard to the duration of depressed excitability following the antidromic firing. Examining the response patterns to OT stimulation of weak intensities, one characteristic difference between the two groups of P cells was found; the fast cells showed the IS without the succeeding LDs whereas the slow cells showed the LDs without the preceding IS. A discussion was made on functional significance of the differentiation of P cells into two types.
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    Experimental brain research 18 (1973), S. 374-382 
    ISSN: 1432-1106
    Keywords: Growth retardation ; Hypothalamus ; Dorsomedial lesions ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Weanling rats received bilateral electrolytic lesions destroying the areas of the ventromedial (VMN) and dorsomedial (DMN) hypothalamic nuclei, respectively. Trunk blood was collected at sacrifice (Experiment 1 and 2∶ 31 days, Experiment 3∶ 14 days) for the determination of plasma growth hormone (GH) by radioimmunoassay. Rats with DMN lesions showed consistently normal to slightly elevated plasma GH levels while animals with VMN lesions showed significantly reduced plasma GH levels. Linear growth was reduced by both types of hypothalamic lesions but body weight gains and food intake were reduced only in the DMN lesioned rats. Carcass fat was greatly elevated in VMN lesioned rats, moderately elevated in one experiment in the DMN animals and normal in another experiment. These data confirm a previous hypothesis that growth retardation in DMN rats is not due to low circulating GH level but rather represents a hypocaloric-type dwarfism.
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    Experimental brain research 17 (1973), S. 133-138 
    ISSN: 1432-1106
    Keywords: Nigro-neostriatal tract ; Rat ; Survival time ; Fink-Heimer method ; Terminal degeneration
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In the morphological demonstration of the nigro-neostriatal tract, there might be some discrepancies between the results by the histofluorescence method and by the degeneration silver method. The present investigation was undertaken to fill the gap by using the modified Nauta Method (Fink-Heimer) to rats surviving for varying periods after unilateral destruction of the substantia nigra. With survival time of 2–3 days, the Fink-Heimer method could demonstrate evenly and densely distributed argyrophilic spheroidal granules in the ipsilateral caudate putamen. These degenerating granules might represent the terminal degeneration of the nigro-neostriatal tract and probably correspond to the result by the histofluorescence method. From 4 days on the terminal degeneration rapidly decreased in amounts or disappeared, leaving a moderate number of beaded coarse fibers, which remained till 2 weeks. The result indicates the possibilities that the degeneration silver method could also be applicable to the demonstration of amine fibers by choosing staining condition and survival time optimal to each animal species and fiber tract.
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    Experimental brain research 16 (1973), S. 466-475 
    ISSN: 1432-1106
    Keywords: Neuroglia ; Radio-autography ; Myelination ; Optic tract ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Resume Une étude, basée sur l'identification et la quantification histologique des cellules névrogliques, a été entreprise dans le tractus optique du Rat sur radio-autographies après injection de thymidine tritiée. Ce bilan a été effectué entre 2 jours et demi et 20 jours après la naissance. D'un point de vue qualitatif, trois catégories cellulaires peuvent être distinguées: les oligodendrocytes, euxmêmes subdivisés en trois classes (grands, moyens, petits), les astrocytes et d'autres varieties cellulaires parmi lesquelles la microglie. D'un point de vue quantitatif, les oligodendrocytes, en particulier les petits, sont largement majoritaires. En effet, sur toute la période examinée les oligodendrocytes représentent près de 81% de la population totale. Sur le plan radio-autographique, l'index de marquage prédomine dans la classe des moyens oligodendrocytes. Ces résultats sont discutés, notamment par rapport aux processus de myélinisation dont les phénomènes de gliose constituent le préambule direct.
    Notes: Summary A study based on the histological identification and quantifying of the neuroglia cells, was carried out in the optic tract of the Rat on radioautographs after injection of tritiated thymidine. The assessment was made two and a half days and twenty days after birth. Qualitatively speaking, three cellular categories can be distinguished: the oligodendrocytes, themselves divided into three sorts (big, medium., small) the astrocytes and other cellular varieties including the microglia. Quantitatively speaking the oligodendrocytes, in particular the small ones, are decidedly more numerous. In fact, over the whole period under consideration the oligodendrocytes represent nearly 81% of the total population. From the point of view of the radio-autography the labeling index predominates in the medium oligodendrocyte group. These results are discussed with reference in particular to the myelination process which is preceded directly by the phenomena of gliosis.
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  • 82
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    Calcified tissue international 13 (1973), S. 113-129 
    ISSN: 1432-0827
    Keywords: Kinetics ; Growth ; Epiphyses ; Hypophysectomy ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La largeur de la métaphyse tibiale, la zone indifférenciée, la zone sériée et les cellules en dégénerescence ont été observées chez des rats Sprague-Dawley normaux et hypophysectomisés. La production cellulaire de la métaphyse est déterminée sur la base de la croissance osseuse longitudinale déterminée par l'oxytétracycline et la taille des cellules en dégénérescence. La diminution de la croissance osseuse longitudinale, en fonction de l'augmentation de l'âge et après hypophysectomie, est due partiellement, à la diminution de production cellulaire et partiellement à une décroissance de la taille des cellules en dégénérescence dans la métaphyse. L'influence de la production cellulaire et de l'activité mitotique prédomine.
    Abstract: Zusammenfassung Die Breite der proximalen Wachstumsplatte der Tibia, deren undifferenzierter und säulenförmiger Zone und die Größe der nahe bei der Metaphyse auftretenden degenerativen Zellen wurden in normalen und hypophysektomierten Sprague-Dawley-Ratten bestimmt. Die Zellproduktion in der Wachstumsplatte wurde aus dem longitudinalen Knochenwachstum berechnet, welches mittels Oxytetracyclin und der Größe der degenerativen Zellen bestimmt wurde. Es wurde festgestellt, daß die Abnahme des longitudinalen Knochenwachstums bei zunehmendem Alter und nach Hypophysektomie zum Teil einem Rückgang in der Zellproduktion, zum Teil einer Verminderung der Größe der degenerativen Zellen in der Wachstumsplatte zuzuschreiben ist. Der Einfluß der Zellproduktion, und somit der mitotischen Aktivität, herrscht vor.
    Notes: Abstract The width of the proximal growth plate of the tibia, its undifferentiated and columnar zone and the size of the degenerative cell close to the metaphysis, were determined in normal and hypophysectomized Sprague-Dawley rats. The cell production in the growth plate was calculated from the longitudinal bone growth determined with oxytetracycline and the degenerative cell size. It was found that the decrease in longitudinal bone growth with increasing age and after hypophysectomy, is due partly to a decrease in cell production, and partly to a decrease in degenerative cell size in the growth plate. The influence of cell production and thus the mitotic activity predominates.
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    Archives of toxicology 30 (1973), S. 187-198 
    ISSN: 1432-0738
    Keywords: Plasma Iron Level ; Side Effect of Drugs ; Rat ; Amphetamine ; Chlorpromazin ; Haloperidolum ; Guanethidin ; Reserpine ; α-Methyltyrosine. ; Plasmaeisenspiegel ; Arzneimittelnebenwirkungen ; Ratte ; Amphetamin ; Chlorpromazin ; Raloperidol ; Guanethidin ; Reserpin ; α-Methyltyrosin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 4 Std nach einmaliger Gabe von 24 mg/kg d,l-Amphetamin i.p. kommt es bei Ratten zu einem Abfall des Eisens im Plasma um 40 bis 60 %. Die Reaktion ist nicht mit dem amphetaminbedingten Anstieg von Körpertemperatur und Skeletmuskelarbeit zu erklären, da sie durch Vorbehandlung mit α-Methyltyrosin, Chlorpromazin, Haloperidol, Guanethidin und Reserpin nicht unterdrückt werden kann. Jedes der zur Vorbehandlung verwandten Medikamente löst selbst bei entsprechend hoher Dosierung eine Hyposiderämie aus. 4 Std nach einmaliger Gabe von 200 mg/kg α-Methyltyrosin vermindert sich der Eisenspiegel im Plasma um 55 %, nach 10 mg/kg Chlorpromazin um 11 %, nach 5 mg/kg Haloperidol um 28 % und nach 20 mg/kg Guanethidin um 50 %. Dieser Effekt ist am ausgeprägtesten mit einer Plasmaeisenverminderung um 69 % 20 Std nach Gabe von 20 mg/kg Reserpin. Als möglicher Pathomechanismus der arzneimittelbedingten Hyposiderämie wird die Wirkung der untersuchten sämtlich zentralnervös aktiven Medikamente als “non-specific stressfull agents” sowie der durch ihre toxische Konzentration in Gang gesetzte Entgiftungsmechanismus im RES diskutiert.
    Notes: Abstract Four hours following a single dose of 25 mg/kg of d, 1-Amphetamine in rats, a 40 to 60 % drop of plasma iron level occurred. This reaction cannot be explained by the Amphetamine-induced rise in body temperature and motor activity, since when pretreated with α-Methyltyrosine, Chlorpromazin, Haloperidolum, Guanethidin and Reserpin this was not observable. All the drugs applied for pretreatment in adequately high doses also induced hyposideremia. Four hours following a single dose of 200 mg/kg of α-Methyltyrosine, plasma iron level was reduced by 55 %, after 10 mg/kg of Chlorpromazin by 11 %, after 5 mg/kg of Haloperidolum by 28 % and after 20 mg/kg of Guanethidin by 50 %. The most pronounced effect (69 % fall) was obtained by 20 hour pretreatment with 20 mg/kg of Reserpin. As possible pathomechanism of the drug induced hyposideremia the applied drugs may be regarded as “non-specific stressfull agents”, or as another possibility, the detoxifying mechanism in RES induced by toxic concentrations of the applied drugs can be considered as responsible for this phenomena.
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  • 84
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    Research in experimental medicine 161 (1973), S. 289-297 
    ISSN: 1433-8580
    Keywords: D-penicillamine ; L-cysteine ; Serum proteins ; Rat ; D-Penicillamin ; L-Cystein ; Serumproteine ; Ratte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In vitro-Untersuchungen zeigten, daß D-Penicillamin durch Serumproteine, in erster Linie durch Albumin, gebunden wird. Aller Wahrscheinlichkeit nach ist die Bildung gemischter Disulfide hierfür verantwortlich. Cystin, L-Cystein und andere Thiole sowie N-Äthylmaleinimid hemmen die Proteinbindung von D-Penicillamin. Verabfolgt man Ratten vor Injektion des D-Penicillamins L-Cystein, resultiert eine vorübergehende Erhöhung des Gehalts an freiem D-Penicillamin in Serum und in einigen Geweben, während die Ausscheidung mit dem Urin verzögert wird. Die theoretische und praktische Bedeutung der Befunde wird diskutiert.
    Notes: Summary Studiesin vitro show that D-penicillamine is bound by serum proteins, mainly albumin; the formation of a mixed disulfide is the most likely explanation. Cystine, L-cysteine and other thiols as well as N-ethylmaleinimide were found to inhibit the protein binding of D-penicillamine. Administration of L-cysteine to rats prior to D-penicillamine brings about a transient increase of the amount of free D-penicillamine in serum and in some tissues as well as a delay in its urinary excretion. The theoretical and practical implications of the findings are discussed.
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    Naunyn-Schmiedeberg's archives of pharmacology 277 (1973), S. 113-138 
    ISSN: 1432-1912
    Keywords: Intestinal Blood Flow ; Intestinal Absorption ; l- and d-phenylalanine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Jejunal loops of anaesthetized rats were perfused (single pass and recirculation) with buffered solutions containing l-phenylalanine (about 30 μM and 30 mM) and d-phenylalanine (about 30 μM). The blood flow, the disappearance rate (from the intestinal lumen) and the appearance rate (in the intestinal venous blood) were determined simultaneously, the accumulation in the gut wall at the end of the experiments. 2. At a constant intermediate blood flow the absorption of l- and d-phenylalanine decreased with time. A decrease of blood flow from about 1.6 to 0.25 ml min−1g−1 wet tissue weight diminished the appearance and the disappearance rate of both isomers. An increase of blood flow from 0.25 to 1.6 ml min−1g−1 caused no increase of absorption; on the contrary the appearance and disappearance rate decreased a little. The different dependence of absorption when decreasing and increasing the blood flow rate may be caused by a changed pattern of blood flow in the layers of the gut wall, i.e. the flow rate in the villi may be reduced while the flow rate in the entire wall remains unchanged. 3. In the single pass perfusion experiments the appearance rate of l-phenylalanine increased proportionally to the luminal concentration (30 μM and 30 mM), while the accumulation was relatively smaller at the high concentration. In the recirculation experiments the appearance rate and the accumulation of l-phenylalanine did not increase proportionally. 4. The increase in perfusion rate, from 0.1 (single pass perfusion) to 2–3 and 10 ml min−1 (recirculation), caused an increase of l-phenylalanine absorption and tissue accumulation. 5. At a luminal concentration of about 30 μM the appearance rates of l- and d-phenylalanine were equal, while the tissue accumulation was smaller for the d-isomer.
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    Naunyn-Schmiedeberg's archives of pharmacology 280 (1973), S. 49-62 
    ISSN: 1432-1912
    Keywords: Corticotropin-Releasing Factor ; Corticoids ; Median Eminence ; Rat ; Histology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In 465 female Wistar rats the influence of an i.m. injection of various natural or synthetic corticoids on the augmentation of “Gomori-positive” granules in the outer layer of the median eminence following bilateral adrenalectomy has been investigated. While the augmentation of the granules is not impaired by progesterone it is inhibited or completely blocked, depending on the dose and the manner of application, by 11-desoxycorticosterone, corticosterone, cortisol, 9α-fluorocortisol, prednisolone, triamcinolone, dexamethasone and fluoroformylone. The doses necessary to suppress the augmentation of the granules correspond to those shown by other authors to be required for blocking ACTH-secretion. The inhibitory effect of the investigated corticoids on the augmentation of the granules is related to their antiphlogistic potency. The findings suggest that the amount of the “Gomori-positive” granules in the outer layer of the median eminence of the rat might be used as a parameter of the activity of the corticotropin-releasing factor.
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    Naunyn-Schmiedeberg's archives of pharmacology 279 (1973), S. 133-152 
    ISSN: 1432-1912
    Keywords: Intestinal Absorption ; Tritiated Water ; Urea ; 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 tritiated water or 14C-labelled urea. The blood flow of the loop was maintained constant at an intermediate rate (0.8–0.9 ml min−1 g−1 wet tissue weight). The water net flux was determined by means of polyethylene glycol as nonabsorbable marker and amounted up to ±30 μl min−1 g−1 w. w. 2. A positive water net flux (directed towards the blood) increased the absorption rates (disappearance rate from the intestinal lumen, appearance rate in the intestinal venous blood) of tritiated water and urea by maximally 22 and 41%, a negative water net flux (directed towards the gut lumen) diminished it by 12 and 32%. 3. The data were analysed by means of a kinetic model with the water net flux as independent variable. The sieving coefficient ⧫=1-δ was 1.18±0.44 for tritiated water and 0.86±0.11 for urea at pH 6.2. The water net flux influenced the absorption of solutes by interaction within the membranes (solvent drag in a restricted sense) and by changing the volume of blood flowing in the capillaries near the epithelium. This last effect is large for the absorption of the rapidly absorbable tritiated water, but small for the absorption of urea which is absorbed ten-times slower. 4. The water net flux in the intestine depended linearly on the osmotic pressure difference between lumen and blood. The hydraulic permeability was 146–180 ml2 min−1 g−1 osm−1.
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    Naunyn-Schmiedeberg's archives of pharmacology 279 (1973), S. 153-172 
    ISSN: 1432-1912
    Keywords: Intestinal Blood Flow ; Intestinal Absorption ; 3-O-Methylglucose ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Jejunal loops of anaesthetized rats were perfused (single pass perfusion and recirculation) with buffered solutions containing 3-O-methylglucose (3-OMG) in two concentrations: below (about 30 μM) and above (about 30 mM) blood glucose concentration. The blood flow, the appearance rate (in the intestinal venous blood) and the disappearance rate (from the intestinal lumen) were determined simultaneously, the accumulation in the gut wall 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 1.8 to about 0.3 ml min−1g−1 diminished the appearance and disappearance rate. An increase of blood flow from about 0.3 to about 1.9 ml min−1g−1 caused no increase of absorption; even a slight decrease was observed. 3. A kinetic analysis of the data showed that the different blood flow dependence of 3-OMG absorption in the experiments with increasing and decreasing blood flow can be explained sufficiently by a decrease of transport capacity with time, presumably due to an altered regional blood flow (decreased villous blood flow rate, unchanged total rate). A postischemic inhibition of 3-OMG absorption was of less importance. 4. The increase in perfusion rate from 0.1 (single pass perfusion) to 10 ml min−1 (recirculation) caused an increase of 3-OMG absorption and tissue accumulation.
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    Naunyn-Schmiedeberg's archives of pharmacology 278 (1973), S. 425-430 
    ISSN: 1432-1912
    Keywords: Brocresine ; Diamine Oxidase ; Rat ; Plasma ; Liver ; Stomach ; Small Intestine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. In male rats DAO was found to be absent in plasma and liver, very low in gastric and high in the upper small intestinal mucosa. 2. Gastric mucosal DAO was completely abolished by 10−8 M Brocresine. In the small intestine inhibition of DAO by Brocresine was dose-dependent, with a concentration of 6.2×10−6 M producing a 50% inhibition of the enzyme. 3. Pretreatment of rats with 100 mg/kg Brocresine i.p. produced a 43% inhibition of DAO after 1 h and an insignificant inhibition by 20% after 4 h. 4. The results suggest that the histidine decarboxylase inhibitor Brocresine is not a very suitable tool for studying the physiological role of histamine by inhibiting its biosynthesis since it also interferes with the histamine catabolism.
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  • 90
    ISSN: 1432-2013
    Keywords: Pulmonary Diffusing Capacity for CO ; Cardiac Output ; Oxygen Dissociation Curve ; High Altitude ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In rats born in the low pressure chamber from sea level parents a higher hypoxic steady-state pulmonary diffusing capacity for CO was found as compared with controls of similar body weight. This difference could be explained by a difference in age or by an increase of blood O2 capacity. There was no difference in alveolar ventilation and alveolar-arterial O2 pressure differences, a lower cardiac output, no difference in arterial O2 tension, no difference in arterial O2 content but a decreased mixed-venous O2 content as compared with control rats measured at hypoxia. A shift of the standard blood O2 dissociation curve to the right was found in the simulated high altitude exposed rats. Calculated mixed-venous O2 pressure was not altered in these rats; since arterial O2 pressure was the same no difference in mean tissue capillary O2 pressure may be presumed as compared with control animals. The results suggest that the first generation of rats exposed to simulated high altitude for their whole life is not only less adapted than animals exposed in their youth (as described in previous work) but that the ability to promote the O2 transport in time of need in rats born in the low pressure chamber is probably even inferior to that of the controls.
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  • 91
    ISSN: 1432-2013
    Keywords: Myoglobin ; Heart ; High Altitude ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Reynafarje's (1963) spectrophotometric method was modified for the study of myoglobin concentration in rat hearts. The influence of age and body weight was evaluated and the age was found to be better correlated with myoglobin concentration than the weight. The influence of simulated altitude of 3500 m was studied in animals exposed to hypoxia at the age of about 34 days and in animals born in the low pressure chamber. In the first group a higher myoglobin concentration was found but only in the right ventricle, together with unilateral hypertrophy, as compared with control animals. In the group of animals born at simulated altitude a severe cardiomegaly developed which was most pronounced in the right ventricle. The myoglobin concentration in the hearts from this group was unchanged in the right ventricle and was lower in the left ventricle and septum.
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    Pflügers Archiv 345 (1973), S. 73-79 
    ISSN: 1432-2013
    Keywords: Gastrosecretagogue ; Gastrin ; Rat ; Bile
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effect of GSP, a gastrosecretagogue fraction extracted from hog pancreas, on bile secretion has been studied in rats provided with a bile duct canula and compared with the effect of antral gastrin. GSP showed no effect on bile secretion, concentration and output of bilirubin and electrolytes in the bile. On the other hand gastrin is significantly increasing bile output, bilirubin concentration and output in the bile. No effect of gastrin on the excretion rate of sodium and potassium in the bile has been observed.
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    Psychopharmacology 28 (1973), S. 87-94 
    ISSN: 1432-2072
    Keywords: Psychopharmacology ; Intragastric ; Self-Administration ; Benzodiazepines ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract A technique for intragastric self-administration in rats is presented. Intravenous self-administration of morphine was compared with intragstric self-administration during 6 consecutive days. There was no difference between the two routes in the total rate of injections. Medazepam was given for intragastric self-administration at three different doses (2.5, 5.0 and 10.0 mg/kg/injection respectively) and compared with saline. There was an increased response rate at the dose 10 mg/kg/injection. Medazepam placebo solution (solvent alone) was also compared with medazepam 10 mg/kg/injection. Among the seven experimental rats, six responded higher on medazepam than on the solvent.
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    Psychopharmacology 28 (1973), S. 243-246 
    ISSN: 1432-2072
    Keywords: δ 1-THC ; Copulation ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The mating behavior of 15 male rats was measured after treatment with δ 1(2)-tetrahydrocannabinol (THC) and propylene glycol (vehicle). Administration of either 2 mg per kg or 3 mg per kg body weight of THC was followed by significant increases in latency to the first mount, latency to ejaculation, and latency to the first mount following ejaculation. No significant changes were found in the number of intromissions or mounts. The deterioration in sexual performance is interpreted as reflecting a decreased motivation to copulate under the influence of the drug.
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    Psychopharmacology 29 (1973), S. 253-261 
    ISSN: 1432-2072
    Keywords: Methamphetamine ; Rat ; Conditioned Aversion ; Saccharin Solution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Holtzman (Sprague-Dawley) rats which were injected in amounts ranging from 0.50–3.0 mg/kg i.p. of methamphetamine avoided a 0.1% saccharin solution which had been paired temporally with the injection, and drank water in a subsequent two-bottle choice situation under non-drug conditions. The aversion persisted for the duration of the experiment, which lasted and obtained whether the animals were fluid-deprived or fluid-satiated. Saline-injected controls, on the other hand, exhibited a 90% saccharin solution preference. Rats which received 0.25 mg/kg contiguous with the drug, or animals given 3.0 mg/kg paired with water, exhibited as extreme a preference for the saccharin solution as did the saline controls. It was concluded that neither a drugmediated taste quality change nor physiological cues associated with thirst were adequate axplanations for the avoidance behavior exhibited, but that the drug was perceived as a noxious stimulus at levels above 0.50 mg/kg under the conditions described above.
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    Psychopharmacology 32 (1973), S. 313-325 
    ISSN: 1432-2072
    Keywords: 6-Hydroxydopamine ; Catecholamine Hypothesis of Depression ; Animal Model ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Two levels of permanent central norepinephrine depletion were obtained in rats by lesioning these neurons with small quantities of intraventricularly-applied 6-hydroxydopamine, and the effects of these lesions on a variety of standard tests of activity and emotional reactivity were studied. Both lesioned groups showed altered emotional reactivity; however, only the animals with less extensive lesions were hyperactive in running wheels, showed heightened shock-elicited aggression, were hyper-responsive to handling, and had a potentiated amphetamine-activation effect. It is suggested that these exaggerated behaviors reflected the sensitization and regeneration of partially lesioned noradrenergic circuits. These data are discussed in terms of the catecholamine hypothesis of depression.
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    Psychopharmacology 29 (1973), S. 85-89 
    ISSN: 1432-2072
    Keywords: Lithium ; Social Isolation ; Spontaneous Activity ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Group-housed rats, injected with an acute dosage of 3 meq/kg lithium chloride, were tested on an activity platform either alone or in pairs 20 min or 3 h after drug administration. Contrary to previous findings, rats administered lithium were less active than those treated with saline after both post-injection periods. However the activity of the saline control animals tested alone after 3 h was considerably less than that exhibited by the same group after 20 min. This activity difference, which could be interpreted as a lithium-social or lithium-time interaction, is more simply explained in terms of the effects of the social isolation occuring between drug administration and testing.
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    Psychopharmacology 32 (1973), S. 351-358 
    ISSN: 1432-2072
    Keywords: Fenfluramine ; FR Responding ; Behavioural Tolerance ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Two experiments on the effects of fenfluramine on FR responding are reported. In Experiment 1 two rats were trained on an FR 10 schedule of reinforcement. After more than 30 h training, intraperitoneal injection of saline, 2, 4 and 8 mg/kg fenfluramine were given. Disruption of the initial stages of responding was noted after 2 and 4 mg/kg, with complete disruption of responding in 1 animal after 8 mg/kg administration. In Experiment 2, 2 rats trained on an FR 30 schedule of reinforcement received chronic 15 days administration of 4 mg/kg fenfluramine. Disruption of responding was noted after the first administration. The degree of disruption lessened by the fifteenth day of administration.
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  • 99
    ISSN: 1432-2072
    Keywords: Rearing ; Locomotion ; Exploratory Behaviour ; Psychotropic Drugs ; Anxiolytics ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The “staircase” is a simple and rapid test and was used to study two components of exploratory behaviour in the rat. The scores of rearing and the number of steps climbed during three minutes were recorded. Various psychotropic drugs were tested, which modified these two parameters. Neuroleptic induced a parallel decrease of both, while benzodiazepines, meprobamate, amobarbitone and ethanol decreased the rearing at doses which left the steps climbed unchanged. At high doses, there was a parallel decrease of both parameters. Amphetamine, at lower doses, increased the rearing score alone. The comparison of the studied psychotropic drug effects with those of two muscle relaxants (by a comparison of the slopes of regression lines) suggests that either the observed benzodiazepine effects were only partly due to their myorelaxant action, or, that both myorelaxants have some anxiolytic action. The effect of amphetamine at low doses can be viewed as a demonstration of increased anxiety.
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    Psychopharmacology 31 (1973), S. 157-166 
    ISSN: 1432-2072
    Keywords: Δ 9-tetrahydrocannabinol ; Predatory Aggression ; Rat ; Serotonin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Δ 9-tetrahydrocannabinol inhibits predatory aggression in rats. Increases in the degree of inhibition are obtained with increasing dosages of the drug. Although sex and strain of the subjects varied nonsystematically, inhibition of predatory aggression uniformly was found to be dose related. Readministration of Δ 9-tetrahydrocannabinol did not effect motor activity measures at dose levels which inhibit aggression. Administration of Δ 9-tetrahydrocannabinol increases whole brain serotonin, while norepinepherine is largely unaffected, indicating that the anti-aggressive effect may be mediated, in part, by serotonergic mechanisms.
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