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  • 1
    Electronic Resource
    Electronic Resource
    Ultracytochemical Localization of Calcium in the Superficial Pineal Gland of the Mongolian Gerbil (1985)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of pineal research 2 (1985), S. 0 
    Details
    ISSN: 1600-079X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: In order to demonstrate fine localization of Ca2+ in the superficial pineal gland of Meriones unguiculatus, the pyroantimonate technique was employed. Control experiments were performed with EGTA and analysis of obtained reaction product using an energy-dispersive x-ray microanalysis.Precipitates of calcium antimonate were formed almost exclusively in swollen clear pinealocytes, in and along their cell membranes, over their nuclei, in mitochondria, the Golgi apparatus, endoplasmic and integrade reticulums. acervuli, in vesicles surrounding synaptic bars, cytoplasmic matrix, and flocculent extracellular material. It has been concluded that the swollen pinealocytes represent a degenerative cell form probably occurring by impairment of plasmalemmal Ca2+-ATPase's ability to eliminate Ca2+ ion from the cell, with consecutive increase of calcium in the cytoplasmic matrix, followed by increase of intramitochondrial Ca2+ concentration, gradual arrest of mitochondrial function, depolymerization of cytoskeletal microtubuli, loss of the cell form, and cell death. Decrease of function of pinealocyte plasmalemma seems to be related to aging.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-079X.1985.tb00625.x
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  • 2
    Electronic Resource
    Electronic Resource
    Histoenzymological Light and Electron Microscopic Localization of Carbonic Anhydrase in the Rat Superficial Pineal Gland (1990)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of pineal research 8 (1990), S. 0 
    Details
    ISSN: 1600-079X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: A histoenzymological method for demonstration of carbonic anhydrase (CA) was used for cryostat sections of superficial rat pineal gland. Light and electron microscopic analysis showed a high concentration of this enzyme in stellate cells, particularly heavily distributed under the organ capsule and scattered in the parenchyma, where they form a widespread three-dimensional network. Most of the pericapillary spaces were lined by CA-reactive cells. The reaction product, in the form of strongly electron-dark precipitates, was localized in the cytoplasmic matrix, whereas organelles, except for some mitochondrial intracristal spaces, were CA-negative. On the basis of localization and morphology of CA-positive cells, we conclude that these represent glial (interstitial) cells.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-079X.1990.tb00672.x
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  • 3
    Electronic Resource
    Electronic Resource
    Calretinin immunoreactivity in pineal gland of different mammals including man (1996)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of pineal research 21 (1996), S. 0 
    Details
    ISSN: 1600-079X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: Calretinin (CR) is a calcium-binding protein, found in a variety of organs and systems such as the central nervous system and the pineal gland. It was first thought to be a specific neuronal marker but this selectivity is now in question since CR has been demonstrated in avian thymus, rat ovary, rat and guinea pig inner ear, rat testis, and chicken and rat pineal gland. To contribute to the knowledge of the presence of CR-positive cells in the pineal parenchyma of rat and other mammalian including man, we performed immunocytochemistry on pineal glands of gerbils, rats, goats, cows, and humans, using a CR anti-serum. To confirm it was actually CR that was demonstrated, we performed Western Blot analyses. Finally, to precisely identify the nature of CR-positive cells we accomplished double-labelling immunofluorescence, using antisera against some nerve cell specific cytosquelettal proteins such as MAP-5, MAP-2, NF-L, NF-M, and NF-H. CR-positive cells were found in all pineal glands studied. These cells all possess a round, oval, or polygonal-shaped perikaryon sending one or more processes of different lengths into the glandular parenchyma. There is a lack of CR immunoreactivity in the nucleus and cell organelles while the cytosol contains a high concentration of this protein. Nevertheless, there are some slight differences between species, especially concerning the number of reactive cells and their relationships with different parenchymal structures such as blood vessels or acervuli. Among the CR-positive cells, only a few were actually nerve cells, contributing probably to an intrinsic innervation of the gland. The remaining CR-reactive cells seem to correspond mostly to pinealocytes in a specific histophysiological state and possibly to neuron-like cells. The significance of the CR-positive cells in the pineal glands remains to be elucidated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1600-079X.1996.tb00279.x
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  • 4
    Electronic Resource
    Electronic Resource
    Morphodynamik der C-Zellen der Schilddrüse und der Parathyreoideazellen der Ratte nach ein- bis achtwöchiger Calcitoninbehandlung (1974)
    Springer
    Anatomy and embryology 144 (1974), S. 19-38 
    Details
    ISSN: 1432-0568
    Keywords: Calcitonin ; C-Cells of the thyroid and cells of the parathyroid glands ; Secondary hyperparathyroidism ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Im Verlauf ein- bis achtwöchiger Behandlung von Wistar-Ratten mit täglich 300 mMRC Einheiten Schweinecalcitonin kam es in den C-Zellen der Schilddrüse, verglichen mit denen der Kontrollserien (unbehandelte und mit Acetatpuffer allein behandelte Tiere), einerseits zu einer morphometrisch signifikanten Abahme der Zahl der Sekretgranula, während andererseits sämtliche Zellorganellen (Mitochondrie,, Golgi-Apparat und auch das granuläre endoplasmatische Reticulum) besser entwickelt waren. In den in gleichen Zeitabschnitten untersuchten Parathyroideazellen fanden wir bei mit Calcitonin behandelten Ratten Strukturveränderungen, die auf eine erhöhte Aktivität hinwiesen: Einfaltungen des Kerns, Erweiterung der Intercellularräume mit Vermehrung und Verlängerung der in diese hineinragenden Mikrovilli, bessere Ausbildung des Golgi-Apparates und des granulären endoplasmatischen Reticulums sowie eine größere Menge freier Ribosomen. Die Zahl der Sekretgranula war eindeutig höher als bei den Kontrolltieren. Der Ca ++- und Mg++-Blutspiegel zeigte während der ganzen Versuchsdauer bei allen Tieren keine statistisch faßbaren Änderungen. Die Autoren vertreten die Hypothese, daß die Aktivierung der C-Zellen durch das Auftreten eines durch die Calcitoninverabreichung hervorgerufenen sekundären Hyperparathyroidismus zustande kommt.
    Notes: Summary Male Wistar rats were injected for one to eight weeks with 300 mMRC units per day of porcine calcitonin. During this period C-cells (or “parafollicular” cells) of the thyroid gland and cells of the parathyroid glands were examined ultrastructurally. The C-cells were further studied morphometrically in animals treated with calcitonin dissolved in acetate buffer as well as in acetate buffer- and not-treated control animals. In the thyroid C cells the number of secretion granules significantly decreased following calcitonin administration, whereas the volume of all cell organelles (mitochondria, Golgi complex and granular endoplasmic reticulum) augmented. The cells of the parathyroid glands of the calcitonin-treated rats showed structural changes due to higher activity: invaginations of the nuclear envelope, enlargement of the intercellular spaces with increase in number and size of the microvilli, better development of the Golgi complex and the granular endoplasmic reticulum, larger population of free ribosomes and secretory granules. However, no significant differences in the blood calcium and magnesium levels were detected when a comparison was made of calcitonin-treated and control animals. All these observations support the hypothesis that the activation of the C-cells may result from a secondary hyperparathyroidism itself induced by the administration of moderate doses of calcitonin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00518631
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  • 5
    Electronic Resource
    Electronic Resource
    Rasterelektronenmikroskopische Untersuchung der Oberflächenveränderungen von Schilddrüsenepithelzellen der Ratte nach 6- bis 48-stündiger Kälteeinwirkung (1978)
    Springer
    Anatomy and embryology 153 (1978), S. 85-93 
    Details
    ISSN: 1432-0568
    Keywords: Scanning electron microscopy ; Thyroid gland (Wistar rat) ; Exposure to cold ; Microvilli
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Rasterelektronenmikroskopische Untersuchungen von Schilddrüsenfollikelzellen von Ratten, die 6 bis 48 Stunden einer Temperatur von +4° ausgesetzt gewesen waren, haben gezeigt, dass, im Vergleich mit denen von bei 22° gehaltenen Kontrolltieren, die Zahl der apikalen Mikrovilli zugenommen hat. Diese Ultrastrukturunterschiede — die 48 Studen nach Versuchsbeginn statistisch signifikant sind — stehen in Beziehung mit der durch die Kälteeinwirkung bedingten Aktivitätssteigerung der Schilddrüse.
    Notes: Summary Scanning electron microscopic observations of thyroid follicle cells of rats exposed to 4° C for 6 to 48 hours were found to show an increased number of apical microvilli in comparison to those of controls kept at 22° C. These ultrastructural differences — which were statistically significant 48 hours after start of the experiments — are related to stimulation of thyroid gland activity by exposure to cold.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00569851
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  • 6
    Electronic Resource
    Electronic Resource
    Ultrastructure of cell death in bulbar cushions of chick embryo heart (1973)
    Springer
    Anatomy and embryology 140 (1973), S. 337-350 
    Details
    ISSN: 1432-0568
    Keywords: Lysosome ; Autophagy ; Phagocytosis ; Acid phosphatase ; Morphogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of the “physiological” cell death was studied in distal ventral bulbar cushions of 15 chick embryo hearts on the 4th and 5th day of incubation. Microperfusion fixation was performed. The ultracytochemistry of a lysosomal hydrolytic enzyme acid phosphatase was also investigated in another 15 embryonic hearts. In the course of the cell degeneration an increase in cellulr autophagy was observed without previous cytoplasmic or nuclear changes or phagocyte ingestion. A cytoplasmic diffusion of acid phosphatase outside of lysosomes was observed. Besides the cell death with the marked participation of the lysosomal system, another kind of dying cells was found, characterized by their nuclear pycnosis and cytoplasmic condensation. Starting from the 5th day of incubation the dying and dead cells were found phagocytized by some of their neighbouring viable mesenchymal cells. A formation of ribosomal crystals was not observed. The formation and fate of cytolysomes as well as the fate of phagocytes are discussed. The presence of pre-necrotic cells with important autophagy and of necrotic cells with nuclear changes was related to the possibility of a dual cause of the cell death. In the case of pre-necrotic cells the epigenetic factors like the biomechanic action of hemodynamics were considered, while the necrotic cells seem to be programmed to death by their genome. Finally the uniformity of cell death ultrastructure in different organs and species was noticed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00525060
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  • 7
    Electronic Resource
    Electronic Resource
    Die Einwirkung von Kälte auf mit Zinkjodid-Osmium tetroxyd reagierende synaptische Bläschen in den Nervenendigungen im Corpus pineale der Ratte (1972)
    Springer
    Anatomy and embryology 135 (1972), S. 301-306 
    Details
    ISSN: 1432-0568
    Keywords: Rat ; Cold ; Pineal gland ; Synaptic vesicles ; Zinc iodide-osmium tetroxide (ZIO) reaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In den synaptischen Bläschen der Nervenendigungen der Epiphyse von Ratten, welche 2 und 4 Tage einer Temperatur von −6° bis −8°C ausgesetzt worden waren, hat man eine signifikante Vermehrung des Zinkjodid-Osmiumtetroxyd (ZIO) reaktiven Materials festgestellt. Der durchschnittliche Durchmesser der ZIO-positiven synaptischen Vesiculae betrug bei den Kontrollratten 234 Å und bei den Ratten, welche 2 und 4 Tage unter der Kälte gelebt hatten, 380 Å, bzw. 379 Å. Die ZIO-Reaktion war bei den Kontrollratten in 49,3% der synaptischen Vesiculae positiv, nach zweitägiger Kälteeinwirkung waren 58,7% und nach viertägiger Kälteeinwirkung 72,1% der synaptischen Vesiculae ZIO-positiv. Auf Grund der vorliegenden Arbeit war es jedoch nicht möglich zu entscheiden, ob die Vermehrung des ZIO-reaktiven Materials mit einer gleichzeitigen Zunahme der biogenen Amine verbunden ist.
    Notes: Summary In the synaptic vesicles of pineal nerve endings of Wistar rats exposed for 2 and 4 days to a temperature of −6° to −8° C, a significant increase of the zinc iodide-osmium tetroxide (ZIO) reactive material was observed. The mean diameter of ZIO reactive synaptic vesicles of control rats was 234 Å; in rats exposed to cold for 2 and 4 days it was 380 Å, respectively 379 Å. In control rats the ZIO reaction was positive in 49,3% of the synaptic vesicles. The reactivity increased to 58,7% in rats exposed to cold for 2 days, and to 72,1% in rats exposed to cold for 4 days. However, the results of the present study do not permit to conclude if an increase of ZIO reactive material is accompanied by a simultaneuos increase of biogenic amines.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00519040
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  • 8
    Electronic Resource
    Electronic Resource
    Weiterer Beitrag zum Vorkommen von dunklen Zellen in der Macula densa des Mittelstückes der Ratten-Niere (1973)
    Springer
    Anatomy and embryology 141 (1973), S. 319-329 
    Details
    ISSN: 1432-0568
    Keywords: Rat kidney ; Macula densa ; Dark and light cells ; Fixation procedure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Verfasser beschreiben die Ultrastruktur der dunklen Zellen in der Macula densa der Mittelstücke der Ratten-Niere nach Perfusionsfixierung in situ. In Vergleich mit den Resultaten aus einer früheren Versuchsreihe mit Immersionsfixierung ist der prozentuale Anteil der dunklen Zellen etwa viermal geringer, während ihre Ultrastruktur im Prinzip die gleiche geblieben ist. Die Verfasser vertreten die Auffassung, daß die dunklen Macula-Zellen nicht unbedingt Präparationsartefakte sind.
    Notes: Summary The authors describe the ultrastructure of the dark cells in the macula densa of the distal convoluted tubule of the rat kidney after fixation carried out by vascular perfusion in situ. In this case the frequency of the dark cells compared with that of the light cells is about four times lower than in previous investigations using the fixation procedure by immersion, whereas the ultrastructure remains essentially unchanged. However, the authors believe that the dark cells of the macula densa are not necessarily artifacts due to the preparation of the specimens for examination in the electron microscope. At present it is not yet possible to decide if the dark and the light cells are two specific cell types of the macula densa or if they represent two different functional stages of a single cell type.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00519050
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  • 9
    Electronic Resource
    Electronic Resource
    Morphometric and enzyme histochemical behaviour of the kidney of young rats before and after unilateral nephrectomy (1976)
    Springer
    Histochemistry and cell biology 46 (1976), S. 107-120 
    Details
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Four week old male Wistar rats were unilaterally nephrectomized, and one, two, four, fourteen, and twenty-eight days after the operation the remaining kidneys were removed for morphological examination—including measurement of diameters of the tubules—and for histochemical investigation of enzymatic activities in the nephrons. The following enzymes were examined: succinate DH, lactate DH, α-glycerophosphate DH, isocitrate DH, glucose-6-phosphate DH, cytochrome oxidase, adenosine triphosphatase, alkaline and acid phosphatases. In comparison with kidneys of control animals of the same age and sex, the hypertrophy of the remaining kidney was found to be, even in these young rats, entirely due to enlargement of preexisting nephrons. The measurements have indicated that the hypertrophy was most distinct between the second and fourth day after uninephrectomy. Four weeks after the operation the diameters of proximal and distal tubules were about 21% and 18% respectively bigger in the uninephrectomized animals than in the corresponding controls. This increase in size was accompanied by some changes in intensity of enzymatic staining reactions; after an intial diminishment, a graduate increase in activity of almost all the observed tubular enzymes was found; this seems to be the expression of the functional compensation by the remaining kidney.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02462735
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  • 10
    Electronic Resource
    Electronic Resource
    Ultracytochemical localisation and comparison of adenyl cyclase activities in pineal bodies of Wistar rats and mongolian gerbils (1977)
    Springer
    Histochemistry and cell biology 53 (1977), S. 249-255 
    Details
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the pineal bodies of Wistar rats and mongolian gerbils (Meriones unguiculati) the main concentration of adenyl cyclase was found in capillary endothelial cells, their basal laminae, pericapillary amorphous material and in nerve endings. In the intercellular clefts between the rat pineal cells there was no adenyl cyclase activity, but a considerable amount of this enzyme was detected in the gerbils. The adenyl cyclase lacks completely in the pinealocyte cytoplasms of both species. It was concluded that the gerbil pineal cells may be more reactive to various hormonal influence than those of the rat.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00511080
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