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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 146 (1974), S. 1-20 
    ISSN: 1432-0568
    Keywords: Placenta ; Cat ; Differentiation ; Function ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé L'ultrastructure du labyrinthe de placenta de chatte a été étudiée du 45e au 63e jour de gestation. Cette formation endothéliochoriale est composée: d'un endothélium maternel hypertrophié et de cellules géantes déciduales; d'une couche de «substance inerte interstitielle»; du trophoblaste constitué d'une assise syncytiale continue (syncytiotrophoblaste) et d'une assise cellulaire discontinue (cytotrophoblaste); d'un endothélium foetal accompagné de son environnement mésenchymateux. Les capillaires foetaux envahissent progressivement le syncytiotrophoblaste. L'hypertrophie de l'endothélium maternel diminue en fin de gestation; de ce fait la distance, séparant le sang maternel du sang foetal, peut atteindre en certains points 2 μ. L'endothélium maternel, le syncytiotrophoblaste et l'endothélium foetal présentent des signes ultrastructuraux d'un rôle de transfert. La «substance inerte inerte interstitielle», qui sépare les tissus d'origine maternelle des tissus d'origine foetale, est constante mais d'épaisseur variable; elle est spécifique des structures endothéliochoriales. Les cellules géantes déciduales, dont le nombre diminue en fin de gestation comportent parfois un ou plusieurs «corps glycogéniques». Le syncytiotrophoblaste, siége d'activité de biosynthése de stéroïdes, est riche en ergastoplasme, ce qui autorise à postuler la synthése d'hormones protéiques.
    Notes: Summary The ultrastructure of feline placental labyrinth has been studied from the 45th to the 63rd day of gestation. The endotheliochorial structure is composed of: a thick hypertrophied maternal endothelium with giant decidual cells; an “interstitial inert substance”; a continuous syncytial layer (syncytiotrophoblast) and a discontinuous cellular layer (cytotrophoblast) of trophoblast; and a thin foetal endothelium with its surrounding mesenchyme. Foetal capillaries increasingly invade the syncytiotrophoblast. Maternal endothelial hypertrophy is reduced in the last days of gestation. Thus the interval between maternal and foetal bloods may in some areas become 2 μ, in late pregnancy. Foetal endothelium, syncytiotrophoblast, and maternal endothelium demonstrate ultrastructural features of transfer function. The “interstitial inert substance”, which separates maternal from foetal tissue was always evident though with variable thickness. The giant decidual cells which are reduced in late pregnancy, show one or several “glycogen bodies”. The syncytiotrophoblast, where some steroïd biosynthesis has been demonstrated, has an extensive rough endoplasmic reticulum suggestive of protein hormone synthesis activity.
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  • 3
    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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  • 4
    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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  • 5
    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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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 147 (1974), S. 35-44 
    ISSN: 1432-0568
    Keywords: Myosatellite cells ; Shark ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The myosatellite cells in the axial muscles of the sharkGaleus melastomus is found more frequently in the red muscle fibers than in the white fibers. The total length of the cell extensions is about 100 μm. In about 20% of all cases, the extensions were present in pairs, and it is concluded that the satellite cell processes bifurcate. Processes towards the intercellular space and towards the interior of the muscle fiber are also described. The cytoplasm of the satellite cells contain glycogen, Golgi elements, lysosome-like vesicles, granular endoplasmic reticulum and microtubules. It is concluded that the morphology of the satellite cells indicates a more active function than that of a dormant reserve myoblast.
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  • 7
    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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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 147 (1974), S. 1-18 
    ISSN: 1432-0568
    Keywords: Mouse kidney ; Thin limbs ; Ultrastructure ; Renal concentrating mechanism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The thin limbs of the loops of Henle in the mouse kidney have been investigated by conventional electron microscopy. Resulting from light microscopic investigations, a distinction in the epithelia of short and long loops can be demonstrated. Ultrastructurally, the thin limbs (descending) of short loops are composed of a uniformly thin and simple epithelium. In contrast, long loops (thin descending and ascending) are composed of three different epithelial types which are representative of a distinctly more complex epithelial system. Two epithelial types were observed in the thin descending limbs of long loops and the third type was observed in the ascending thin limbs. Based upon these findings it is suggested that the thin descending limbs of short and long loops of Henle in the mouse kidney cannot perform the same functions in the renal concentrating mechanism.
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  • 9
    ISSN: 1432-0568
    Keywords: Oocyte ; Follicle cells ; Intercellular bridges ; Lizard ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Intercellular bridges connect the oocyte with its surrounding follicle cells. 2. Fibrillar bundles and microtubules are oriented along the length of the bridge. Mitochrondria, endoplasmic reticulum, multivesicular vesicles and other cytoplasmic components are also present in this region. 3. This communication may be very important for the flow of nutrients necessary for the growth of the oocyte.
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  • 10
    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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  • 11
    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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  • 12
    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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  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 146 (1974), S. 219-224 
    ISSN: 1432-0568
    Keywords: Leydig cells ; Differentiation ; Explants ; Ultrastructure ; Mouse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Testes of newborn mice not older than one day were transplanted into the anterior chamber of one eye of an adult male white Holtzman rat. The events observed in the Leydig cells of the grafted testes can be divided into two periods. Period one is marked by differentiation; period two, by dedifferentiation. In period one, the lipid and glycogen inclusions disappear, possibly owing to the gonadotropins of the host. In period two, which starts after day 15 post-grafting, the lipids and glycogen reappear; the Leydig cells now contain residual bodies, whereas the S.E.R. disappears. Immunological mechanisms can be implicated; it is suggested that the Leydig cells dedifferentiate because the host's gonadotropins may be incapable of evoking and/or activating the genetic memory of the grafted Leydig cells.
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  • 14
    ISSN: 1432-0568
    Keywords: Baboon ; Cleavage stages ; Embryos ; Preimplantation ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé La structure et l'ultrastructure des embryons de babouin sont étudiées dans la période précédant l'implantation. Six stades du développement embryonnaire sont observés 2, 3, 4, 5, 7 et 8 jours après la date présumée de fécondation. Dans les 3 premiers cas, on compte respectivement 2, 8 et 24 blastoméres. A 5 jours, il y a 30 à 40 cellules et un nombre dépassant 60, ultérieurement. Des cellules trophoblastiques primitives se différencient à 7 jours et une cavité de segmentation en forme de croissant apparaît au 8 ème jour. La zone pellucide est toujours présente à 8 jours, la période de préimplantation semblant plus longue chez le babouin que chez l'homme. Des particules de type C sont décrites dans la zone pellucide et les espaces périvitellin et interblastomériques. La transformation des mitochondries, des changements dans la répartition des ribosomes, des corps multivésiculaires, pseudocristallins et figures myéliniques, des nucléoles et amas granuleux intra-nucléaires s'observent chez le babouin comme chez certains autres Mammifères; par contre, les faisceaux fibrillaires cytoplasmiques sont absents. L'étude des changements de l'ultrastructure provoqués par des hormones et drogues permettrait de mieux évaluer la nocivité de ces substances pendant les premiers stades du développement embryonnaire des Primates.
    Notes: Summary The baboon preimplantation stages were examined using light and electron microscopy. Six cases were studied at 2, 3, 4, 5, 7 and 8 days estimated fertilization age. The first 3 specimens were composed of 2, 8 and 24 blastomeres respectively. At 5 days, 30 to 40 cells were counted and more than 60 cells in later stages. Primitive “trophoblast cells” differentiate at 7 days and a crescentic blastocoele appears at 8 days. Shedding of the zona pellucida is not observed in the 7 and 8 day specimens. The preimplantation period is longer in the baboon than in man. C-type viruses are observed in the zona pellucida, in the perivitelline and interblastomeric spaces. Microvilli and caveolae cover the periphery of the baboon conceptus. As in many other mammals, transformation of the mitochondria, changes in the ribosomes distribution, multivesicular bodies, myelin figures, nucleoli and intranuclear clusters of granules are described in the baboon. Cytoplasmic fibrous strands are not present as in the mouse. Experiments on the influence of hormones and drugs on ultrastructural changes would help to evaluate the importance of biohazards during the early development of primates.
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  • 15
    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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  • 16
    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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  • 17
    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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  • 18
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    Acta neuropathologica 28 (1974), S. 25-35 
    ISSN: 1432-0533
    Keywords: Chronic Lead Intoxication ; Rat ; Ultrastructure ; Microglia ; Pericytes ; Monocytes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Wistar rats of both sexes and the same litter were exposed to chronic lead intoxication from birth untill sacrifice 9 months later. Lead was administered as 0.4% solution of lead nitrate in drinking water. Samples from the parietal brain cortex were examined electron microscopically following intracardiac perfusion with paraformaldehyde-glutaraldehyde solution. Similar changes were observed in the microglial cells and the vascular pericytes whereas all the other tissue elements appeared intact. Both cell types hypertrophied, the microglia assumed characteristic spindle or rod shape, the cell organelles increased, the microglial endoplasmic reticulum widened strongly and a large number of lipid inclusions appeared. The latter consisted of large lipid droplets of varying size and shape, containing multiple zones of low density, and a dense component with a coarse granular structure. The similarity in the response of both cell entities to the lesion as well as some probable functions of microglial cells and their relationship to vascular pericytes are discussed.
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  • 19
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    Acta neuropathologica 29 (1974), S. 251-262 
    ISSN: 1432-0533
    Keywords: Polymyositis ; Ultrastructure ; Histiocytes ; Birbeck Granules ; Macrophages
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A fatal case of polymyositis in a young female is presented. Two muscle biopsies obtained before and after treatment with large doses of steroids, as well as autopsy tissue, demonstrated widespread degeneration of myofibres associated with cytoplasmic tuboreticular structures resembling paramyxovirus nucleocapsids in capillary endothelial cells and fibroblasts. Aggregates of spherical particles and “simple and granular” nuclear bodies suggested a virus-related or associated etiologic agent. In addition, interstitial cells of mesenchymal origin, probably related to macrophages or histiocytes were present. These contained numerous rodlike profiles or phagolysosomal bodies which resembled “Birbeck” granules. Inflammatory response was very scant. It would appear that polymyositis probably represents a primary reaction to antigemic substances and a morphologic manifestation of altered host macrophage response.
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  • 20
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    Acta neuropathologica 30 (1974), S. 225-242 
    ISSN: 1432-0533
    Keywords: Ultrastructure ; Optic Nerve ; Schilder's Disease ; Devic's Disease ; Disseminated Sclerosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of the optic nerve is described and compared in: a)Schilder's Disease, b)Devic's Disease, c)Disseminated Sclerosis. a) Schilder's Disease. Parts of the nerve were demyelinated, sometimes extensively so and from these regions the oligodendrocytes had disappeared and there was proliferation of astrocytes. Parallel bundles of fibres with a “railway line” formation, occurred in the cytoplasm of the astrocytes. Phagocytes infiltrated the damaged nerve bundles and the fibrous septa between them. Osmiophilic particles occurred in the astrocytes, capillary endothelial cells and in the phagocytes. The collagen fibres of some septa were widely separated presumably by fluid. b) Devic's Disease. This condition occurred in a patient with active pulmonary tuberculosis. The nerve was extensively demyelinated and showed absence of oligodendrocytes, proliferation of astrocytes and infiltration by macrophages. Some astrocytes possessed Rosenthal fibres. Intranuclear inclusions occurred in the astrocytes and electron dense cytoplasmic inclusions in the capillary endothelial cells and the macrophages. c) Disseminated Sclerosis. Parts of the nerve were partially and other parts completely demyelinated. Oligodendrocytes were absent from the completely demyelinated zones but were present in the partially demyelinated zones. In and around the demyelinated regions, there was proliferation of astrocytes and they frequently exhibited the “railway line” patterns in their cytoplasm. Phagocytes were frequent amongst the degenerating myelin and the proliferating astrocytes and also in the fibrous septa. Some macrophages presented intranuclear inclusions having a “corn on the cob” appearance.
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  • 21
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    Acta neuropathologica 30 (1974), S. 287-294 
    ISSN: 1432-0533
    Keywords: Lead Toxicity ; Brain ; Cerebral Endothelium ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of cerebral vessels was studied at various stages of brain development in chick embryos exposed to lead intoxication when they were 4 days old. The endothelial cells showed swelling of mitochondria, presence of many cytolysosomal structures, many tubular bodies, and coated vesicles. A few vessels showed attenuation on the lining endothelial cells. The significance of these morphological alterations are discussed.
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  • 22
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    Acta neuropathologica 30 (1974), S. 277-285 
    ISSN: 1432-0533
    Keywords: Chick Embryo ; Brain ; Blood Vessels ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structure of the blood vessels was studied in the developing brain of chick embryo. The blood vessels were present in the embryos first examined (4 days after incubation) and their number increased in subsequent stages. The endothelial cells were generally large and showed junctional complexes, many microvilli and a large number of cytoplasmic organelles. Many tubular bodies and coated vesicles were also present. The tubular bodies were sometimes noted near the Golgi apparatus, suggesting their origin from this organelle. The mitochondria in the endothelial cells were generally larger than those in the surrounding neuropil. An ill-defined basement membrane-like substance was noted outside some endothelial cells on the 11th day and well formed basement membrane was present in the vessels of 18 day old embryos. A complete subpial astrocytic basement membrane was present from the early stage studied (4 days).
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  • 23
    ISSN: 1432-0533
    Keywords: Malignant Lymphoma ; Blood Vessels ; Lymphe Node ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structure of the blood vessels of an apparently primary intracerebral malignant lymphoma was compared with those in another malignant lymphoma in a retroperitoneal lymph node. The essential features of the blood vessels in both cases were the same. They resembled the blood vessels found in normal lymph nodes and were both distinctly different from those seen in normal brain. It was concluded that the direction of differentiation of the blood vessels which arise to nourish the neoplastic tissue is determined by the nature of the tumor rather than the vessels from which they originate.
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  • 24
    ISSN: 1432-0533
    Keywords: Myoclonic Epilepsy ; Atypical Myoclonus Body (Type II) ; Histochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Histochemical studies of type II myoclonus bodies demonstrated that they were composed of a saccharide-lipid complex with a small amount of protein. In particular, they contained phospholipid, ganglioside and sphingomyelin. The ultrastructure of the bodies revealed that they were bound by a membrane. They were diffusely stippled or homogeneous. They were not formed of filaments or lamellae. Some correlation with microbody or lysosomal structures in association with degeneration of the neurone was suggested.
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  • 25
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    Acta neuropathologica 28 (1974), S. 79-86 
    ISSN: 1432-0533
    Keywords: Ultrastructure ; Human Outer Cortex ; Pia Mater
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The pia mater consists of a single, interrupted layer of elongated cells which lie fairly close to the surface of the cortex. Granular material and some collagen fibres lie between the pial cells and the cortex, a greater amount of collagen being present where the pial cells are discontinuous. Basement membrane covers the outer aspect of the cortex, the outer layer of which is formed by interlacing astrocyte processes of varying size. The processes are closely applied with occasional desmosomes between them. Projections of astrocyte processes of different dimensions covered by basement membrane extend at irregular intervals from the cortex into the subarachnoid space.
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  • 26
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    Acta neuropathologica 28 (1974), S. 87-92 
    ISSN: 1432-0533
    Keywords: Neuroaxonal Dystrophy ; Hallervorden-Spatz Disease ; Mitochondria ; Axonal Swelling ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Multifocal central white matter axonal swelling characterized electron microscopically by focal axonal mitochondrial and membraneous body enrichment occurred in a 52 year old man who presented with the chief complaint of severe progressive muscular weakness accompanied by disorientation. The clinical and pathological findings in this patient appear unique and are presented in order to broaden our concepts of axis cylinder pathology.
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  • 27
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    Acta neuropathologica 27 (1974), S. 61-68 
    ISSN: 1432-0533
    Keywords: Muscular Pathology ; Ultrastructure ; Abnormal Muscular Inclusion ; Fingerprint Bodies ; Myofilament Synthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary “Fingerprint bodies” are added to the “atypical” formations described in diseased muscle. These subsarcolemmal inclusions are variable in size and number, not membrane-bound and are formed by fine microtubules. They are not characteristic of a specific muscular disease and occur probably along with a focal anomaly of myofilament synthesis.
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  • 28
    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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  • 29
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    Acta neuropathologica 27 (1974), S. 363-368 
    ISSN: 1432-0533
    Keywords: Parallel and Concentric Tubules ; Arachnoid Cells ; Cerebral Glioma ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Parallel and concentric tubules were observed in the cytoplasm of arachnoid cells overlying cerebral gliomas. The parallel tubules were 400–500 Å wide. Their electron dense walls, 150 Å thick lay 200–250 Å apart with distensions up to 400 Å in diameter at irregular intervals between the walls. The walls formed terminal loops limiting up to 4 adjacent tubules; transverse extensions were present between adjacent walls. The tubules sometimes communicated with the rough endoplasmic reticulum from which they may possibly arise. The concentric tubules were 250 Å wide: they communicated at irregular intervals.
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  • 30
    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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  • 31
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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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  • 32
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    Journal of molecular medicine 52 (1974), S. 559-567 
    ISSN: 1432-1440
    Keywords: Progressive myoclonus epilepsy (Lafora's disease) ; Type I (Unverricht, Lundborg) ; Type II ; Liver findings ; Clinical aspects ; Histology ; Ultrastructure ; Histochemistry ; Biochemistry ; Glycogenosis type IV ; Progressive Myoklonusepilepsie (Laforasche Erkrankung) ; Typ I (Unverricht, Lundborg) ; Typ II ; Leberbefunde ; Klinik ; Histologie ; Ultrastruktur ; Histochemie ; Biochemie ; Glykogenose Typ IV
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Dem klinischen Bild der progressiven Myoklonusepilepsie (Lafora's disease) liegt eine kongenitale Stoffwechselanomalie mit Ablagerung pathologischer Stoffwechselprodukte vorwiegend im Zentralnervensystem zugrunde. Der häufigere Typ I (Typ Unverricht, Typ Lundborg) zeigt eine regelmäßige Mitbeteiligung von Leber und Myokard sowie teilweise der Muskulatur, der seltenere Typ II ist mit seiner Speicherung nur auf das Zentralnervensystem beschränkt. Die Kenntnis der charakteristischen Leberbefunde kann einmal eine Hilfe sein für die klinische Unterscheidung von Typ I und Typ II, unspezifisch degenerativen Formen der Myoklonusepilepsie sowie gegenüber der myoklonischen Variante der amaurotischen Idiotie. Als eine weitere Möglichkeit könnte das bisher unbekannte Speicherprodukt und der auslösende spezifische Enzymdefekt auf diesem Wege identifiziert werden. Lichtmikroskopisch zeigen die Leberzellen — vorwiegend der Läppchenperipherie — und gelegentlich auch die Kupfferschen Sternzellen eine PAS-positive homogene Speichersubstanz, die in Übereinstimmung mit den Befunden am Zentralnervensystem und am Myocard elektronenoptisch aus granulärem und filamentärem Material aufgebaut ist. Die Deutung der einzelnen Untersucher hinsichtlich der histochemischen und biochemischen Ergebnisse variiert: die Natur des Ablagerungsproduktes wird als Mucopolysaccharid aber auch als Polyglucosan angesprochen. Übereinstimmend sieht man aber die Hauptstörung im Bereich des Kohlenhydratstoffwechsels. Die hier demonstrierten bemerkenswerten licht- und elektronenmikroskopischen Übereinstimmungen mit der Glykogenose Typ IV lassen nach unserer Auffassung nahe Beziehungen zur Gruppe der Glykogenosen annehmen. Als Thesaurismose ist die Laforasche Erkrankung eine potentielle Vorstufe der Cirrhose. Es entwickelt sich eine mehr oder minder ausgeprägte Mesenchymbeteiligung im Sinne einer chronischen Hepatitis. Eine komplette Cirrhose ist jedoch selbst bei den Spätfällen nicht nachzuweisen. Eine Hepatomegalie als Folge der Speicherung fehlt. Spezifische Leberproben fallen negativ aus. Das klinische Bild wird nicht von Seiten der Leber, sondern ausschließlich von der progredienten neurologisch-psychiatrischen Symptomatik der Myoklonusepilepsie geprägt.
    Notes: Summary The cause of clinical manifestations of progressive myoclonus epilepsy (Lafora's disease) is an inborn error of metabolism characterised by deposition of pathologic metabolic products in the central nervous system. In the most common type I (Type Unverricht, Type Lundborg) these deposits are regularly located in liver and myocard, and in some cases also in sceletal muscle. In the less common type II they are found only in the central nervous system. The characteristic liver findings might help to distinguish type I, type II, unspecific degenerative forms of myoclonic epilepsy and the myoclonic form of amaurotic idiocy. They also might be valuable in identification of yet unknown specific enzyme defect leading to tissue deposits. Our light microscopy observations demonstrate deposits of a PAS-positive homogene substance in liver cells—especially in the periphery of lobule— and sometimes in Kupffer cells. By electron microscopy this substance is identified as granular and filamentary material. This corresponds to our findings in the central nervous system and myocard. The interpretation of existing histochemical and biochemical studies did not yet solve the question, if the mentioned deposits are mucopolysaccharides or polyglucosanes, however, it is recognized that the main disorder is an error in carbohydrate metabolism. The notable similarity of our light- and electronmicroscopic observations to results obtained in glycogenosis type IV suggest that Lafora's disease might be another form of glycogenosis. As a thesaurismosis Lafora's disease can predispose to cirrhosis. The activation of mesenchyme, less or more pronounced, corresponds to chronic hepatitis. And even in the late forms a complete cirrhosis is not found. This thesaurismosis does not lead to hepatomegaly. Specific liver function tests are negative. The clinical course is characterised not by liver symptoms but by the neurologic and psychiatric symptoms of progressive myoclonic epilepsy.
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  • 33
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    Archives of microbiology 96 (1974), S. 145-153 
    ISSN: 1432-072X
    Keywords: Ultrastructure ; Scenedesmus Bristles ; Openings ; Props ; Ridges ; Tubules ; Brisble Origin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Bristles radiating from openings were detected on colonies and unicells ofScenedesmus culture N 46, when examined with transmission and scanning electron microscopes. Although narrower, they correspond in gross appearance and ultrastructure to previously describedScenedesmus bristles. Openings, bordered by a series of props, are unlike those ofScenedesmus culture 614. Additional props are observed scattered independently on the cell wall; ridges are composed of a linear row of props. Sections of cells, or cell walls, reveal an additional prop, situated inside the openings; these props are composed of several tubules. Possible extrusion of bristles through these tubules, as well as the origin of the bristle from the cavity and vesicles immediately under the opening are discussed.
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  • 34
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    Archives of microbiology 96 (1974), S. 271-279 
    ISSN: 1432-072X
    Keywords: Anabaena cylindrica ; Nitrogen Starvation ; Pigmentation ; Ultrastructure ; Heterocyst Differentiation ; Nitrogenase Activity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Nitrogen starvation, effected by incubating a culture ofAnabaena cylindrica in a medium free from combined nitrogen and under an atmosphere of 1% CO2 in argon, leads to rapid and characteristic changes in the appearance, structure and function of the alga. Change of colour, due apparently to a decrease in the amounts of nitrogenous pigments, is accompanied by a structural transformation of vegetative cells: cyanophycin granules and polyhedral bodies disintegrate, lipid and glycogen accumulate, and large membrane-bound spaces form by means of thylakoid swelling and vesiculation. The rate of heterocyst differentiation and nitrogenase activity is increased. These changes are fully reversed on addition of ammonia to the culture. It appears that thylakoids reform by coalescence of small vesicles assembled in the intrathylakoidal space. Rapid ammonia assimilation is indicated by ample formation of cyanophycin granules in vegetative cells and of “plugs” in the heterocysts.
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  • 35
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    Archives of microbiology 99 (1974), S. 221-230 
    ISSN: 1432-072X
    Keywords: Anabaena cylindrica ; Molybdenum ; Vanadium ; Nitrogenase ; Ultrastructure ; Storage Products ; Heterocyst Frequency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The structural and functional symptoms of molybdenum deficiency inAnabaena cylindrica grown in a medium without combined nitrogen and thus dependent on fixation of elemental nitrogen, resemble those brought about by nitrogen starvation. However, the substantially increased rate of heterocyst differentiation in this culture is not accompanied by a corresponding increase in nitrogenase activity; on the contrary, enzyme activity is severely impaired in the absence of molybdenum. When the supply of molybdenum, or of ammonia, is restored, the alga recovers rapidly. Vanadium exerts an inhibitory effect upon nitrogen-fixing ability of the alga, and its presence in the molybdenum-deficient culture results in the amplification of the symptoms of mlybdenum deficiency.
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  • 36
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    Archives of microbiology 99 (1974), S. 265-269 
    ISSN: 1432-072X
    Keywords: Ultrastructure ; Microbodies ; Vacuolaria ; Gonyostomum ; Chloromonadophyceae ; Chromophyta
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Microbody-like organelles occur in the cytoplasm of two chloromonadophycean algae,Vacuolaria virescens Cienkowsky andGonyostomum semen Diesing. Microbodies ofVacuolaria andGonyostomum have a granular matrix which lacks a crystalloid core; they are often present in close association with elements of the endoplasmic reticulum. The occurrence of microbodies in other algae is briefly reviewed.
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  • 37
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    Archives of microbiology 99 (1974), S. 331-344 
    ISSN: 1432-072X
    Keywords: Myxomycetes ; Ultrastructure ; Development ; Systematics ; Food Vacuoles ; Stalk Development
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Observations of sporophore development in fresh and glutaraldehydeosmium sequentially-fixed material ofProtophysarum phloiogenum show the following sequence. Small plasmodia cease streaming and round up. Food vacuoles collect in the lower center of the cytoplasmic mass. As the cytoplasm rises the food vacuolar contents are excluded from the plasmalemma and become the stalk core. A continuous, fibrous peridium and stalk tube enclose cytoplasm and stalk core respectively. Capillitial formation just precedes spore cleavage. Sporophore development is marked by autophagic activity and calcium deposition. Stalks of dried herbarium specimens of seven additional species have been examined. A mature stalk morphology very similar toProtophysarum with recognizable remnants of microorganismal food material is seen in all of them. It is thought that this marker is indicative of non-stemonitaceous stalk development.
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  • 38
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    Archives of microbiology 100 (1974), S. 419-436 
    ISSN: 1432-072X
    Keywords: Gloeobacter violaceus ; Photosynthetic Pigments ; DNA Base Composition ; Fatty Acid Composition ; Cyanobacterium ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Gloebacter violaceus gen. and sp. n. is a unicellular photosynthetic prokaryote of unusual cellular structure. The only unit membrane in the small, rod-shaped cells is the cytoplasmic membrane, which has a simple contour, without intrusions. Immediately underlying it is an electron-dense layer 80 nm thick. Gloeobacter is an aerobic photoautotroph which contains chlorophyll α, β-carotene and other carotenoids, allophycocyanin, phycocyanin and phycoerythrin. Chlorophyll and carotenoids are associated with the particulate fraction of cell-free extracts, and are thus probably localized in the cytoplasmic membrane. The phycobiliproteins may be associated with the electron-dense 80 nm layer. The DNA contains 64.4 moles percent GC. The cellular lipids have a high content of polyunsaturated fatty acids, largely linoleate and γ-linolenate. Despite its atypical fine structure, Gloeobacter is evidently a cyanobacterium, sufficiently different from other unicellular cyanobacteria to be placed in a new genus.
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  • 39
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    Archives of microbiology 96 (1974), S. 175-182 
    ISSN: 1432-072X
    Keywords: Ultrastructure ; Septa ; Schizophyllum ; Dissolution
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A strain ofSchizophyllum commune carrying a mutation in theB-mating factor (B-mut) shows septal dissolution when grown at 30° C for 2 to 3 days. The septa are intact if the organism is grown at 25° C for the same time, but begin to break down within 1 h after transfer to 30° C. At the ultrastructural level the dolipore swelling is the first part of the septal apparatus to be degraded, closely followed by the disorganization of the parenthesomes. A progressive thinning of the septal cross-wall produces an enlargement of the septal aperture sufficient to allow the passage of nuclei. It appears that degradative enzymes are probably carried to the site of septal dissolution in vesicles derived from endoplasmic reticulum in the area of the septal apparatus.
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  • 40
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    Archives of microbiology 96 (1974), S. 305-317 
    ISSN: 1432-072X
    Keywords: Marine Fungi ; Ultrastructure ; Multilamellate Sporangial Wall ; Sagenogenetosome ; Zoospore Cleavage
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The morphology and ultrastructure of aJaponochytrium sp. has been studied by light, scanning and transmission electron microscopy. The wall has been shown to be multilamellate and persistent. Stages in zoospore cleavage are described and sagenogenetosomes reported in mature sporangia.
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  • 41
    ISSN: 1432-072X
    Keywords: Streptomycetes ; Ultrastructure ; Surface Sheath
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract 1. Tubular-like structures were regularly revealed in the surface sheath of the aerial mycelium of the parent strain of Streptomycetes roseoflavus var. roseofungini. In their shape and dimensions these structures were highly reminiscent of those massive accumulation of which was earlier reported to occur in cultures of dedifferentiated nocardioform “fructose” mutant of the same parent strain. 2. The tubular-like structures of the aerial mycelium sheath were shown to be markedly susceptible to brief acetone washing, undergoing almost complete desintegration. 3. On addition of water to crude acetone extract of the aerial mycelium precipitation and possible selfassembly of a spectrum of various structures occurred (folded scaly, bubble-like, spout-like). Some among structures so produced were reminiscent of those found in spectra of structures observed in reconstruction experiments with tubules from the mutant as well as of structures found in the aerial sheath of the parent strain and some other actinomycetes. Similarity in subunit structure of above materials was also noticeable. The presence, in the sheath of aerial mycelium, of material with a tendency to selforganization is discussed in relation to the possible involvement of selfassembly processes in the formation of the surface sheath.
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  • 42
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    Archives of microbiology 101 (1974), S. 95-107 
    ISSN: 1432-072X
    Keywords: Zoophagus insidians Rotifer ; Predacious Fungi ; Oomycetes ; Glue Secretion ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The predacious watermold Zoophagus insidians traps loricate rotifers on short, lateral branches of the main, hyphal axis. These branches or “traps” are packed at their distal ends with a number of vesicles filled with an electron-dense matrix. Electron micrographs of the mycelium disclose a two-layered wall; the outer layer is electron dense and the inner, electron transparent. The outer dense layer on the tip of the “trap” is organized into a number of fine ridges and occasional discontinuities. Thin sections through recently trapped rotifers indicate that the cilia of the animals are stuck to the trap by a glue. This adhesive is derived from secretion of the matrix of the vesicles aggregated in the tip of the trap. The secretion mechanism is triggered by the animal and is accompanied by: 1. The separation of the two layers of the wall, 2. fusion of the vesicles with the cell membrane and 3. extrusion of the glue through pits in the tip of the inner wall of the “trap”. After snaring a rotifer, the previously arrested branch grows as a haustorium into the body cavity of the animal. The host tissues disintegrate within a few hours and appear to be the main nutrient source of the fungus.
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  • 43
    ISSN: 1432-072X
    Keywords: Bdellovibrio bacteriovorus ; Spirillum serpens ; Freeze Fracture ; Electron Microscopy ; Ultrastructure ; Membrane Damage ; Organismic Associations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The freeze-fracture technique and electron microscopy have been used to demonstrate that localized damage is inflicted upon the cytoplasmic membrane of Spirillum serpens VHL within 20 to 30 min after the start of its association with Bdellovibrio bacteriovorus 109D. This damage is not observed in uninfected Spirillum cells, nor in infected cells within the first 10 min. This damage takes the form of a “blister” which, when viewed stereoscopically in electron micrographs, is seen to project toward the interior of the Spirillum cell. Shortly after its formation, the blister becomes elaborated into a series of ridges which may assume forms ranging from an elaborate spiral to a series of loops or knots. The formation of a blister is shown to involve both the inner and outer leaves of the membrane bilayer, and evidence is presented to indicate that the blister site corresponds to the site of attachment of the Bdellovibrio cell. The hypothesis is proposed that this ultrastructural damage is the cytological basis for the controlled and localized leakage through the cytoplasmic membrane into the periplasmic space of the Spirillum cell at locations adjacent to the Bdellovibrio cell. It is suggested that this localized membrane damage may be the ultrastructural basis for the high efficiency with which bdellowvibrios are known to incorporate cytoplasmic materials from the other bacteria in whose periplasmic spaces they develop.
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  • 44
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    Archives of microbiology 98 (1974), S. 199-206 
    ISSN: 1432-072X
    Keywords: Ultrastructure ; Chlamydomonas ; Senescent ; Microtubules ; Complexes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Complexes of twisted ribbons composed of ordered arrays of microtubules are identified in close association with the plasmalemma and the surfaces of some organelles in senescent cells of photoheterotrophically cultured Chlamydomonas dysosmos. The ribbon complexes occur throughout the cytoplasm, and do not appear related to the flagellar insertions. The component microtubules are approximately 26 nm in width, exhibiting a center-to-center spacing of about 44 nm. Additional cytoplasmic microtubules are often closely related to the tubular complexes. A detailed description of their fine structure is presented here which tends to support the ascribed function of microtubules in maintaining the structural integrity of the protoplasm.
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  • 45
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    Archives of microbiology 98 (1974), S. 147-158 
    ISSN: 1432-072X
    Keywords: Allomyces ; Zoospores ; Cell Wall ; Wall Formation ; Lomasome ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Ultrastructural observations on encysting haploid zoospores of Allomyces arbuscula are presented with special reference to cell wall deposition. Multivesicular bodies are observed in the cytoplasm of zoospores 15 min after inoculation, lomasomes after 30 min and fine membrane profiles between the plasmalemma and the cyst wall are observed after 4 h indicating a possible system for secretion of cell wall components.
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  • 46
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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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  • 47
    ISSN: 1432-1106
    Keywords: Brain cortex slices ; Ultrastructure ; Fluid spaces ; Swelling
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A comparison was made between morphological and biochemical estimates of extracellular and intracellular fluid spaces in rat brain cortex slices incubated under different conditions. By light microscopy the periphery of the slices was found to be more swollen than the center; this regional difference was verified biochemically in unfixed tissue. The electronmicroscopic evaluation of intra- and extracellular fluid spaces was accordingly based upon findings in a preselected area. Due to intracellular penetration of inulin in rat brain cortex slices the biochemically, determined extracellular and intracellular spaces were obtained by compartmental analysis of the inulin space. The concordance between the biochemical and the morphological findings was good: Both methods showed that the extracellular space increased during the incubation to a considerable magnitude after one hr. and that this extracellular space was reduced by excess potassium, glutamate, anoxia or incubation at 0°. Under the same conditions the biochemically determined intracellular space was increased. This cellular swelling was confirmed morphologically and found to comprise mainly glia cells after exposure to excess potassium, predominantly neurons after incubation at 0° and both cell types after anoxia or addition of glutamate.
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  • 48
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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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  • 49
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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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  • 50
    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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  • 51
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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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  • 52
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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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  • 53
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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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  • 54
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    Research in experimental medicine 164 (1974), S. 1-17 
    ISSN: 1433-8580
    Keywords: Pathology ; Ultrastructure ; Smooth muscle ; Ulcus ventriculi ; Pathologie ; Ultrastruktur ; Glatte Muskulatur ; Ulcus ventriculi
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wurde die glatte Muskulatur des Antrum ventriculi sowie des Pylorus von 7 Patienten mit einem oder mehreren Ulcera ventriculi untersucht. Vergleichsweise konnten die entsprechenden Regionen des Magens von 5 normalen Organspendern der elektronenmikroskopischen Präparation zugeführt werden. Elektronenoptisch faßbare Veränderungen fanden sich noch 180 mm von der Ulcusläsion entfernt an den glatten Muskelzellen der inneren Rings- und der äußeren Längsmuskulatur sowie an den Gefäßen. Eine regelmäßig anzutreffende Veränderung der glatten Muskelzellen des Antrum und des Pylorus besteht in einer Strukturverdichtung des Kerns, der sarkoplasmatischen Grundsubstanz und der Myofilamente, kombiniert mit einer Vermehrung und Vergrößerung der hypolemmalen Vesikel, wie der dense bodies. Die Befunde werden als Ausdruck einer starken isometrischen Kontraktion der glatten Muskulatur im Antrum und im Pylorus bei Ulcera ventriculi gedeutet. Die geschilderten Befunde ließen sich an normalem Untersuchungsmaterial nicht erheben. Neben für das Magenulcus unspezifischen pathologischen Befunden an den glatten Muskelzellen, wie Anhäufung von Lipofuscin im Endoplasmahof und Lyse der Myofilamente, konnten spezifische Veränderungen gefunden werden. Diese betreffen die nur im Endoplasmahof differenzierten Räume des endoplasmatischen Reticulums. Bei zahlreichen Muskelzellen der Rings- und Längsmuskelschicht kommt eine extrem starke Quellung des endoplasmatischen Reticulums zur Beobachtung. Die Vacuolisation der endoplasmatischen Räume führt zu einer Verdrängung der übrigen Zellorganellen sowie der Myofilamente. Die Capillarendothelzellen weisen degenerative Veränderungen auf, die zu einem Sistieren cytopemptischer Vorgänge führen. In der arteriolären Gefäßstrecke findet sich vielfach eine starke Kontraktion der glatten Muskulatur bis zum völligen Verschluß der Gefäßlichtung. Auch diese Befunde ließen sich nur an den Mägen mit Ulcera ventriculi, nicht dagegen an dem normalen Vergleichsmaterial erheben.
    Notes: Summary The smooth musculature of antrum and pylorus of 7 patients with one or more stomach ulcers was examined by transmission electron microscopy. Corresponding regions of the stomachs of 5 normal organ donors served as control material. Electronmicroscopically visualizable changes were found at distances of up to 180 mm from the site of ulcerous lesion on the smooth muscle cells of the inner circular and outer longitudinal musculature, also on the blood vessels. A regularly occurring modification of the smooth muscle cells of antrum and pylorus consists of a structural condensation of the nucleus, of the sarcoplasmic ground substance and of the myofilaments, combined with augmentation and distension of the hypolemmal vesicles and of the dense bodies. These findings are interpreted as expression of a pronounced isometric contraction of the smooth musculature in the antrum and pylorus in presence of ulcera ventriculi. Such findings are not obtainable on normal material. Besides pathological modifications at the smooth muscle cells which are unspecific for stomach ulcer, such as accumulation of lipofuscin in the endoplasmatic lacunae and lysis of the myofilaments, specific changes were observed. These concern the interstices of the endoplasmic reticulum to be found only in the endoplasmatic lacunae. In numerous muscle cells of the circular and longitudinal muscle layers an extremely marked distension of the endoplasmic reticulum is found. Vacuolization of the endoplasmic cisternae causes displacement of the other cell organelles and of the myofilaments. The capillary endothelial cells show degenerative changes which bring about arrest of cytopemptic processes. In the arteriolar regions a strong contraction of the smooth musculature, at times resulting in complete occlusion of the vasal lumen, is frequently found. These findings, too, are obtainable only on stomachs with ulcera ventriculi and not on normal control material.
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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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    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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    Pflügers Archiv 352 (1974), S. 1-10 
    ISSN: 1432-2013
    Keywords: Thermoreceptors ; Cold Receptor ; Ultrastructure ; Receptor Morphology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Afferent impulses were recorded from single fibers serving cold and warm receptors in the skin of the cat's nose. The receptors were carefully tested for specificity and the receptive fields localized under the microscope with a microthermode. Each single fiber served one spot-like receptive field. The field was marked without damaging the nerve ending by inserting two thin stainless steel wires into the skin on both sides of the receptor. Investigation of semithin and ultrathin serial sections by light and electron microscopy revealed beneath each cold spot a dermal papilla which contained a single small myelinated fiber dividing into a number of unmyelinated terminals. Near the epidermis the receptor branches leave their Schwann cell envelope, penetrate the basal lamina of the epithelium, and their tips are invaginated into the cytoplasm of the basal epithelial cells. The basal lamina of the epithelium fuses with that of the receptor axon. The receptor axons contain numerous mitochondria, glycogen particles and a filamentous receptor matrix with vesicles of various sizes. The described structures were absent beneath the warm spots. In addition to the cold receptors, Merkel cell neurite complexes and lamellated encapsulated endings were found that are known to be mechanoreceptors.
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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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    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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    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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    Calcified tissue international 15 (1974), S. 201-212 
    ISSN: 1432-0827
    Keywords: Ultrastructure ; Alkaline Phosphatase ; Calcification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Des cals expérimentaux de neuf jours, formés au niveau de radius de jeunes rats, sont traités par la méthode calcium-cobalt de Gomori (1939) pour la mise en évidence ultrastructurale de la phosphatase alcaline afin d'étudier son rôle éventuel dans le dépôt du calcium. L'activité enzymatique apparait initialement sous forme de précipités globulaires en dehors de la membrane cellulaire de jeunes chondroblastes hypertrophiques. Ce précipité donne ensuite naissance à des corps sphériques de phosphatase alcaline qui se forme près de la cellule. Ces corps sphériques s'observent dans une zone intermédiaire plus éloignée. Une formation de cristaux en aiguilles (apparemment une calcification) se développe dans des corps isolés ou agrégés, laissant voir nettement leurs limites, même lorsque la calcification est plus avancée au point qu'on ne peut plus distinguer des cristaux individuels. Au niveau des coupes témoins, traitées de façon identique mais sans substrat ou avec de l'E.D.T.A., on n'observe ni précipité enzymatique ou corps sphériques. L'aspect des dépôts cristallins dans des corps qui contiennent de la phosphatase alcaline ne peut s'expliquer que par l'existence d'une association étroite entre enzymes et calcification.
    Abstract: Zusammenfassung Neun Tage alter experimenteller Kallus an Radii von jungen Ratten wurde mit Gomori's (1939) Calcium-Kobalt Methode untersucht, um die Verteilung der alkalischen Phosphatase und ihre Beziehung zur Calciumablagerung ultrastrukturell zu demonstrieren. Enzymaktivität zeigte sich zuerst als globulares Präzipitat außerhalb der Zellmembran von Knorpelzellen im Beginn der Hypertrophie. Aus dieser Präzipitatschicht entstanden dann gerundete Körperchen, die sich von der Zelle abtrennten. Solche Körperchen wurden auch in größerer Entfernung von der Zelle beobachtet, d.h. in einer Zwischenzone zwischen benachbarten Zellen. Nadelförmige Kristalle, wahrscheinlich von Calcium-Salzen, wurden in einzelnen oder aggregierten Körperchen beobachtet. Die äußere Zone der Körperchen blieb jedoch deutlich sichtbar, selbst dann, wenn der Calciumgehalt derart zugenommen hatte, daß einzelne Kristalle nicht länger erkennbar waren. In Kontrollen, die in gleicher Weise behandelt waren, aber ohne Substrat oder mit Zufügung von EDTA, wurden weder Präzipitate noch Körperchen beobachtet. Das Auftreten von Calciumablagerungen in alkalischer Phosphatase enthaltenden Körperchen scheint kaum anders erklärbar als durch eine enge funktionelle Verbindung zwischen Enzym und Calciumablagerung.
    Notes: Abstract Nine day old experimental calluses in radii of young rats were treated with Gomori's (1939) calcium-cobalt method to demonstrate ultrastructurally the presence of alkaline phosphatase in a search for its possible role in the desposition of calcium. Enzyme activity first appeared as globule-like precipitates outside the cell membrane of early hypertrophic cartilage cells. This precipitate layer then seemed to give rise to spherical bodies of alkaline phosphatase which occur at a slight distance from the cell. The spherical bodies were also observed further away from the cell in an intermediate zone between neighboring cells. Needle-like crystal formation, apparently calcification, occurred inside single or aggregated bodies, leaving their peripheral rim clearly visible, even when calcification had increased to such an extent that individual crystals could no longer be recognised. In controls, treated in the same way but without substrate, or with EDTA, no enzyme precipitate or spherical bodies were seen. The appearance of crystalline deposits in bodies which contain alkaline phosphatase seems difficult to explain on any other basis than that there is a close functional association between the enzyme and calcification.
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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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    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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    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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    Naunyn-Schmiedeberg's archives of pharmacology 281 (1974), S. 175-196 
    ISSN: 1432-1912
    Keywords: Intestinal Absorption ; Basic Drugs ; Amidopyrine ; Antipyrine ; Solvent Drag ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Jejunal loops of anaesthetized rats were perfused with hypotonic, isotonic and hypertonic buffered solutions containing 14C-labelled amidopyrine and antipyrine at neutral and at acidic pH. The blood flow of the loop was maintained at an intermediate rate (0.7–1.0 ml min−1g−1). The water net flux was determined by means of polyethylene glycol as non-absorbable marker and amounted up to ±30 μl min−1g−1. 2. A positive water net flux (directed towards the blood) increased the appearance rate of amidopyrine and antipyrine by maximally 43.8 and 49.2%, a negative water net flux (directed towards the gut lumen) diminished it by 38.8 and 35.0%. 3. The experimental data were analysed by means of a kinetic model with the water net flux as independent variable and the epithelial permeability kF D , the serosal permeability k S F S and the sieving coefficient Φ=1−σ as absorption parameters. For antipyrine independent of the pH-value of the perfusion solution kF D was 0.123, and, for amidopyrine at pH 7 and pH 3 kF D was 0.231 and 0.091, respectively. k S F S was zero indicating that in this experimental arrangement the transfer of drug molecules to the serosal side was negligible. The sieving coefficient Φ amounted to 2.30 for amidopyrine and 2.15 for antipyrine at neutral pH. At acidic pH it amounted to 0.50 for amidopyrine and 1.44 for antipyrine. The hydraulic permeability of water was identical at neutral and acidic pH. 4. The high sieving coefficient for the two drugs at neutral pH is interpreted as indicating that water and lipophilic drug molecules interact within the lipid part of the cell membrane. At acidic pH the ionized drug molecules appear to permeate the cell membrane preferentially across other (presumably more hydrophilic) areas.
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    Naunyn-Schmiedeberg's archives of pharmacology 286 (1974), S. 165-179 
    ISSN: 1432-1912
    Keywords: Lipidosis ; Antidepressants ; Neuroleptics ; Lymphocytes ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Lymphocytes of rat lymph nodes have previously been revealed as reliable and sensitive indicators of a particular drug side effect, notably a generalized phospholipidosis, inducible by a compound of amphiphilic character (chlorphentermine). The purpose of the present study was to examine the effects of other amphiphilic compounds upon rat lymphocytes. After oral administration of various tricyclic antidepressants (iprindole, imipramine, clomipramine, 1-chloro-amitriptyline, 1-chloro-10,11-dehydro-amitriptyline, noxiptiline, amitriptyline), or of two neuroleptic drugs (chlorpromazine, thioridazine) to rats, the popliteal lymph nodes were examined with the electron microscope. After a single application of either iprindole (50 mg/kg), imipramine (100 mg/kg), or clomipramine (150 mg/kg) small proportions of lymphocytes were found to contain abnormal lamellated cytoplasmic inclusions. The size and number of inclusions and the number of affected lymphocytes increased with further treatment. Similar observations were made after treatment with the chlorinated amitriptyline derivatives. On the other hand, only small numbers of lymphocytes were affected by noxiptiline, amitriptyline, chlorpromazine and thioridazine, even after prolonged treatments (up to 13 weeks) with high doses (up to 125–175 mg/kg). The present ultrastructural finding are interpreted as representing lipidosislike cellular alterations, yet of highly varying degrees. The large quantitative differences are tentatively suggested to be due to differences in the rate and mode of metabolism of the drugs, and due to differing degrees of amphiphilia of the compounds applied.
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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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  • 68
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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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  • 69
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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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  • 70
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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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  • 71
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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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  • 72
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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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  • 73
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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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  • 74
    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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  • 75
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    Keywords: Rat ; Chlordiazepoxide ; Diazepam ; Extinction ; Avoidance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract In a one-way avoidance task with rats, injections of Librium (chlordiazepoxide) following avoidance acquisition resulted in prolonged resistance-to-extinction of the avoidance response. This effect occurred regardless of whether the rats had had prior experience with Librium or whether they were naive with respect to the drug. The same results were found with the same task when low doses of Valium were used. However, at a higher dosage an “extreme reaction” of either no responding or a high number of responses to extinction occurred in the naive animals. The Librium and Valium effects were compared to similar effects obtained using ethanol and hashish resin. These results indicate that the novelty hypothesis as originally stated by Amit and Baum cannot be supported because experience with the drugs prior to avoidance training did not attenuate the drug effect on avoidance.
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  • 76
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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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  • 77
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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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  • 78
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    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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  • 79
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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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  • 80
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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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    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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    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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  • 83
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    Cell & tissue research 148 (1974), S. 309-311 
    ISSN: 1432-0878
    Keywords: Cecum ; Colon ; Lanthanum ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary After exposure of mouse cecal mucosa to lanthanum during primary fixation in glutaraldehyde, the metal was found as discrete particles covering microvilli and microorganisms, as a continuous layer outlining the lateral surfaces of epithelial cells, and as particles bound to collagen fibrils. The results suggest that lanthanum acts primarily as a stain of the surfaces of certain cells and extracellular structures, and to a lesser extent as an inert probe of the extracellular space.
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  • 84
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    Keywords: Ovary ; Blue fox ; Lutein cells ; Plasma progesterone ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary An electron microscopic investigation of the lutein cells of the blue fox was undertaken, based on the hypothesis that differences in plasma progesterone levels at differing stages of pregnancy might be reflected in the ultrastructural organization. Comparisons were made between corpora lutea taken from animals mated 1, 2, 5, 14, 18, 20, 28, 33, 36, 39 and 45 days after the estimated time of ovulation. Measurements of progesterone on plasma samples were performed by a rapid competitive protein-binding assay. During the period with increasing and/or high plasma progesterone levels, (i.e. 1 to 14 days after ovulation) the lutein cells are characterized by evenly distributed cisternal agranular ER, mitochondria with both tubular and lamellar cristae, and electron-dense lipid droplets. The abundant agranular ER is closely associated with the lipid droplets and mitochondria. During the period with declining plasma progesterone levels, the lutein cells present a different morphological picture: the agranular ER assumes the form of bundles of parallel tubules disposed in several planes. During the latest stages observed, these “bundles” are disrupted and most of the agranular ER become arranged in smaller concentric whorls. Both kinds of whorls regularly enclose lipid droplets, dense bodies and mitochondria. The regions between the whorls contain scattered cisternae of endoplasmic reticulum, ribosomes, mitochondria and lysosome-like dense bodies.
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  • 85
    ISSN: 1432-0878
    Keywords: Supraoptic and paraventricular nuclei ; Ultrastructure ; Osmotic stimulus ; Quantitative study
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Substitution of a 2% solution of sodium chloride in place of drinking water for 3 days significantly increased both the size of neurosecretory neurones in the supraoptic and paraventricular nuclei of rats and the proportion of these cells which had dilated endoplasmic reticulum. There was an increase in the number of multivesicular bodies per mean cell profile and also an increase in the ratio of “dense” (immature) to “pale” (mature) neurosecretory granules within the perikarya, although the total numbers of granules were unchanged. If, after 3 days of saline-treatment, the rats were again allowed tap water to drink for 2 days, the proportion of cells showing dilated endoplasmic reticulum and the number of multivesicular bodies returned towards normal, but there was a significant increase in the number of large dense lysosomal bodies per cell profile and a relative increase in the proportion of “pale” (mature) neurosecretory granules. These changes suggest that the increased bio-synthetic activity resulting from saline-treatment subsides when the treatment is terminated. Furthermore, since neurohypophysial hormone stores have still not returned to normal in animals of the recovery group, they also imply the absence of an internal feedback system by which the level of neural lobe hormone stores might govern the synthetic activity of the neurosecretory cells. Both the increased synthesis, and the increased electrical activity which accompanies it, may be independent consequences of the depleting stimulus.
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  • 86
    ISSN: 1432-0878
    Keywords: Photoreceptors ; Nervous system ; Polychaete ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Organs of presumed photoreceptor significance in Nephtys exhibit great simplicity. The pigmented eyes of Nephtys are embedded in the posterior region of the brain. Each consists of a pigment cup and two closely-associated sensory cells. The cells exhibit the characteristic features of rhabdomeric-type photoreceptor structures. The anterior or accessory eyes are identical to the pigmented eyes except that each may consist of only a single cell and that pigment cups are absent. A pair of “sensor sacs” is also present, embedded in the brain. Each consists of a single cell which has the appearance of possessing a large intracellular vesicle (the phaosome) into which project irregularly arranged microvilli. The limiting membrane is, in fact, continuous with the cell membrane. Evidence is presented of the secretion of material of unknown character into the vesicle.
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    Cell & tissue research 151 (1974), S. 79-92 
    ISSN: 1432-0878
    Keywords: Adenohypophysis ; PMS-primed rat ; FSH gonadotrope ; LH gonadotrope ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The existence of distinct FSH and LH gonadotropes has been suggested by several investigators whereas others have supported a one-gonadotrope hypothesis. To obtain further clarification on this subject, ultrastructural studies of pituitaries and radioimmunoassays of serum FSH, LH and prolactin were carried out in the PMS treated immature rat. The surge of FSH began at 12 noon on day 32 with a maximum at 6 pm that continued into the next day, while the LH maximum was reached at 4 pm. The serum levels of prolactin also began to rise at 12 noon on day 32 but did not reach maximum until 8 am of day 33. FSH cells as defined earlier by Costoff (1973) were well granulated at 12 noon and at 4 pm on day 32. At this later time many FSH cells exhibited extensive Golgi complexes, hypertrophied vacuolar endoplasmic reticulum and often times greatly swollen mitochondria. At 7 PM of day 32 many FSH cells were in various stages of degranulation. LH cells were enlarged and well granulated prior to 12 noon of day 32 but thereafter appeared degranulated. On day 31, prolactin cells were enlarged and well granulated. Although these cells contained extensive endoplasmic reticulum and Golgi complexes, there were few mature granules during day 32 and in the early morning hours of day 33. At 1 PM of day 33 most of the FSH and LH, and some prolactin cells were again granulated. These studies correlating ultrastructure with FSH and LH levels in the serum of PMS treated rats further suggest the existence of two distinct gonadotropes in the rat, one producing FSH and another LH.
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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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  • 89
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    Cell & tissue research 153 (1974), S. 63-77 
    ISSN: 1432-0878
    Keywords: Smooth muscle ; Intestine ; Afferent fibres ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The innermost layer of the circular musculature of the ileum of the guinea-pig, mouse, rat, rabbit, cat and dog is made of special small and dark muscle cells (sd cells), which can be identified by light and electron microscopy. These cells have a higher surface to volume ratio than ordinary muscle cells. They show all the organelles of smooth muscle cells and are in close relationship with a great number of extrinsic and intrinsic nerve fibres. They send numerous thin cytoplasmic processes towards the bulk of the circular layer, but nexuses between the sd cells and ordinary muscle cells are not found. It is suggested that some of the nerve fibres in this part of the circular layer are motor, setting the sd cells to a given length, and some are afferent in luminal pressure.
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  • 90
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    Cell & tissue research 150 (1974), S. 271-279 
    ISSN: 1432-0878
    Keywords: Heavy bodies ; Oogenesis ; Maturation ; Sea urchin ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary An ultrastructural study of in vitro maturation of A. punctulata oocytes was undertaken to determine when heavy body formation was initiated. No heavy bodies were seen in germinal vesicle oocytes or in oocytes undergoing germinal vesicle breakdown or polar body formation. Heavy bodies were only observed in ova examined one to two hours after pronuclear formation. Several small heavy bodies were seen in sections of eggs fixed as early as three hours after the pronucleus had formed. The number of these structures in the egg cytoplasm increased with time. Therefore it is concluded that heavy body formation in sea urchin ova is a phenomenon following nuclear maturation.
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  • 91
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    Cell & tissue research 150 (1974), S. 343-368 
    ISSN: 1432-0878
    Keywords: Fertilization ; Gametes ; Echinoid ; Echinarachnius ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The morphology of gametes of a representative echinoid, Echinarachnius parma were investigated ultrastructurally with particular emphasis on gamete interaction during fertilization. The acrosomal region of the spermatozoon is characterized by the presence of two components: an acrosomal vesicle and periacrosomal materials. The acrosomal vesicle, which is completely bounded by a limiting membrane, is surrounded by periacrosomal materials. Nuclear and mitochondrial regions of the spermatozoon are also described briefly. The ovum is surrounded by two extraneous coats: an outer jelly layer and an inner vitelline envelope. Pigment cells are present within the outer jelly layer. Ooplasmic organelles and inclusions including cortical granules and the female pronucleus are described. Spermatozoa undergo the acrosomal reaction in the vicinity of mature ova. Events of acrosomal reaction, including dehiscence of the acrosomal vesicle and acrosomal tubule formation, are described and summarized schematically. Acrosomal vesicle contents remain adherent to the outer surface of the tubule membrane. Primary binding of the spermatozoon to the surface of the ovum is accomplished by the establishment of morphological continuity between this extracellular coat and the vitelline envelope of the ovum. It is suggested that the species specificity of fertilization resides in this primary binding of gametes. Membrane fusion, between the tip of the acrosomal tubule and the colemma, follows primary binding and cytoplasmic continuity of the gametes is thereby established. It is concluded that the early events of fertilization in Echinarachnius parma generally conform to the Hydroides-Saccoglossus pattern of the Colwins (1967).
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  • 92
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    Cell & tissue research 153 (1974), S. 277-292 
    ISSN: 1432-0878
    Keywords: Ultrastructure ; Pineal Gland ; Mole ; Paracrystalline structures
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les pinéalocytes (au sens strict: Wolfe, 1965) de l'épiphyse de la Taupe (animal vivant pratiquement toujours dans une complète obscurité) examinés au microscope électronique, ont été comparés à ceux d'autres Mammifères. Dans le périkaryon des mitochondries, des ribosomes, du réticulum endoplasmique lisse et granulaire et quelques lysosomes et inclusions lipidiques sont présents. La présence à l'intérieur de certaines cavités du réticulum endoplasmique granulaire et parfois entre les deux feuillets de l'enveloppe nucléaire, de structures paracristallines (de nature protéique ?) est caractéristique des pinéalocytes de cet animal. L'appareil de Golgi sécréte des vésicules claires de 500 à 1500 Å de diamètre. Quelques très rares grains de sécrétion, dont l'origine golgienne n'a pas encore été démontré, ont été observé dans le périkaryon et à l'extrémité de certains prolongements. Un grand nombre de structures ciliaires (9+0 paires de tubules) ont également été observés dans les pinéalocytes.
    Notes: Summary The ultrastructure of the mole pinealocytes, a mammal which lives practically in complete darkness, has been examined and compared with that of other mammals. Mitochondria, ribosomes, smooth and granular endoplasmic reticulum, lysosomes and lipid incluclusions are present in the perikaryon. The presence of a paracrystalline structure of a possibly proteinaceous nature in some cisterns of the granular endoplasmic reticulum and between the two layers of the nuclear membrane, is characteristic of the mole pinealocyte. The Golgi complex produces clear vesicles of 500–1500 Å in diameter. Occasionally, some dense core secretory vesicles were observed in the perikaryon and in the ending of cell processes. Their presumed origin from the Golgi complex could not yet be demonstrated. A large number of ciliary derivatives (9+0 pattern) are also present in the mole pinealocyte.
    Type of Medium: Electronic Resource
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  • 93
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    Cell & tissue research 153 (1974), S. 339-355 
    ISSN: 1432-0878
    Keywords: Sertoli cell, human ; Morphological classification ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary As revealed by light microscopical investigations the human Sertoli cell presents different appearances according to the pattern of infranuclear cytoplasmic inclusions. Although two or three stages of spermatogenesis are seen in a single cross section of a seminiferous tubule the Sertoli cells all show virtually the same features in such a cross sectioned tubule. The different appearances are also evident under the electron microscope. Although no obvious correlation was found with the stages of spermatogenesis in the seminiferous epithelium, the Sertoli cell appearances described here may be assumed to represent different metabolic situations. Other features of Sertoli cell ultrastructure are discussed such as the presence of residual bodies in the apical cytoplasm, glycogen-rich areas protruding towards the tubular lumen or the extracellular space, and membrane bound, round structures, found between the membranes of the smooth endoplasmic reticulum and resembling the “microbodies” of steroid producing cells.
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  • 94
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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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  • 95
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    Cell & tissue research 155 (1974), S. 541-554 
    ISSN: 1432-0878
    Keywords: Hypophysectomized rats ; Reorganized stalk ; Ultrastructure ; Salt load
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The reorganized stalk of hypophysectomized rats, either “intact” or subjected to a 6-day salt load, has been studied by light and electron microscopy. PAF-positive neurosecretory material is seen mainly in the periphery of the reorganized stalk, usually in 2–5 μ nerve swellings of animals operated two months before. Nerve swellings make contact with a dense capillary network. Three types of nerve fibres and their swellings are distinguished according to the size of elementary granules. Peptidergic A1 and A2 types contain granules with a maximum diameter of 170 and 130 nm respectively; monoaminergic B type fibres have granules of 100 nm in diameter. A1 type axonal swellings are the most numerous and can be tentatively divided into four subtypes according to their ultrastructure and relationships with capillaries and pituicytes. Swellings of types b and c, making direct contact with capillaries or pituicyte perikarya, usually contain few granules and numerous synaptic vesicles arranged frequently in clusters in the “active” zones. It is assumed that they are especially active in the release of peptide neurohormones. It is also hypothesized that in the hypophysectomized rats peptide neurohormones are released not only directly into the pericapillary space but also into the intercellular cleft, especially at sites of neuron-pituicyte junctions. Nerve swellings of type a, separated from the pericapillary space by thin pituicyte processes, usually contain numerous neurosecretory granules. It is suggested that vascular “end-feet” of pituicytes may somehow reduce neurohormone release. The depletion of PAF-positive material as well as the decreased granule content even after a salt load of only 1 per cent shows that the reorganized stalk is functional as a neurohaemal organ, but has a diminished hormone reserve. This, together with a primitive cytomyeloangioarchitecture speaks for morphological and functional imperfection of the reorganized stalk.
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  • 96
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    Cell & tissue research 153 (1974), S. 517-530 
    ISSN: 1432-0878
    Keywords: Medial preoptic area ; Hypothalamus ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The neuronal and glial cell bodies and the neuropil of the medial preoptic area of the rat hypothalamus were studied under the electron microscope. Two different types of neurons are identified on the basis of electron density. These two types differed in a number of ultrastructural features. Three types of nerve terminals based on vesicle morphology are also described, as well as the general structure of the axons, dendrites and synapses in the neuropil. The structure of oligodendrocytes and astrocytes is also discussed.
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  • 97
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    Cell & tissue research 154 (1974), S. 39-49 
    ISSN: 1432-0878
    Keywords: Gobius jozo (Teleost) ; Testis ; Steroidogenic tissue ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The homologue of mammalian Leydig cells in the testis of fish of the genus Gobius is believed to be a glandular mass lying along the mesorchium and quite distinct from the seminiferous region. This gland was studied in Gobius jozo by light and electron microscopy. Histologically, the gland is composed of cords of polyhedral cells located between the main vessels of the testis and the deferent duct. Dark and light cell varieties were observed both after staining with toluidine blue and with respect to their cytoplasmic electron density. The fine structure of the glandular cells is characterized by a well developed agranular endoplasmic reticulum in the form of random anastomosing tubules and vesicles and by very numerous mitochondria with tubulo-vesicular cristae. In some mitochondria the internal organization is paracrystalline. One or two bodies of unknown nature are Found in the Golgi region. They are partially limited by an unusually thick membrane and contain a material subdivided mostly into small vesicles. Liposomes and lipofuscin pigment granules are also present. The ultrastructural features of the glandular cells of the testis of Gobius jozo confirm a specialization in steroid hormone production.
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  • 98
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    Cell & tissue research 148 (1974), S. 69-82 
    ISSN: 1432-0878
    Keywords: Ultimobranchial glands ; Anuran larvae ; Metamorphosis ; Ultrastructure ; Scanning electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of ultimobranchial (UB) gland cells from Rana temporaria larvae 48 h after hatching until the completion of metamorphosis is described. A single UB cell type is present, believed to be the characteristic C cell, in which secretory granules are first detectable in 8 day post-hatching larvae. These secretory granules show an intimate association with lipid droplets. Unusual membranous and crystalloid inclusions, which may represent yolk platelets, are found in UB glands of very small larvae. The significance of a range of UB organelles is discussed and some scanning electron micrographs presented. This report is believed to be the first published ultrastructural and scanning electron microscope study of larval anuran UB glands.
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  • 99
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    Cell & tissue research 148 (1974), S. 381-396 
    ISSN: 1432-0878
    Keywords: Placenta ; Mouse ; Syncytium ; Morphogenesis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'origine embryologique des constituants cytologiques de la barrière placentaire chez la Souris a été mise en évidence du 8ème au 11éme jour de la gestation et la séquence des phénomènes favorisant la formation d'un syncytium trophoblastique, précisée. La barrière placentaire trilaminaire a une double origine: la couche interne provient du trophoblaste chorionique, la couche médiane syncytiale comme la couche externe dérivent du trophoblaste ectoplacentaire. Le stimulus initial de la différenciation semble résulter au 9ème jour du contact entre le trophoblaste chorionique et le mésoderme allantoïdien. Quelques heures après, on observe la réaction des cellules chorioniques, caractérisée par une augmentation importante des nucléoprotéines cytoplasmiques, puis l'apparition de globules lipidiques et enfin des propriétés de motilité. Ces cellules établissent des jonctions complexes avec le trophoblaste ectoplacentaire indifférencié qu'elles côtoient. En même temps, le métabolisme nucléaire de ces cellules ectoplacentaires semble modifié. Ultérieurement, au 10éme jour de la gestation, la disparition des membranes plasmiques latérales de ces cellules, conduit à la formation d'un syncytium par fusion de cellules au même stade d'évolution.
    Notes: Summary The morphogenesis of the different layers forming the mouse placental barrier is described during the 8th to 11th day of gestation. The timing and events leading to the formation of the syncytiotrophoblast are analyzed. Two different processes lead to the formation of the hemotrichorial placental membrane: the internal layer is formed by the chorionic trophoblast, both the intermediate syncytial layer and the external cytotrophoblast layer are derived from the ectoplacental trophoblast. The differentiation of the placental barrier begins on the 9th day of gestation by the establishment of contact between the chorionic trophoblast and the allantoic mesoderm. A few hours later, the chorionic cells show a considerable increase in cytoplasmic nucleoproteins and lipids and become ameboid. Complex cell-junctions differentiate between these chorionic cells and the adjacent ectoplacental trophoblast. On the 10th day of gestation the lateral cytoplasmic membranes disappear leading to the formation of a syncytium.
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  • 100
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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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