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  • 101
    ISSN: 1432-0878
    Schlagwort(e): Pars distalis ; Graft ; Ultrastructure ; Prolactin ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Intact female rats received transplants of two hypophysial partes distales under the kidney capsule. The plasma levels of prolactin were determined, and the ultrastructure of the grafted gland was studied 15, 45 and 90 days after the operation. Although prolactin levels in the three experimental groups were significantly higher than those in control rats, a decrease in prolactin level was detected in the 45-day samples. Parallel ultrastructural changes suggest that between the 45th and 90th postoperative day a process is initiated leading to hyperplasia and hypertrophy of prolactotrophs.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 102
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 711-715 
    ISSN: 1432-0878
    Schlagwort(e): Gastric antral mucosa ; Caerulein ; Gastrointestinal hormones ; Cholecystokinin ; Trophic effect ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The growth-promoting effect of caerulein on antral gastric mucosa was explored using Wistar rats. Implanted osmotic minipumps were used to administer submaximal doses of either caerulein or saline to normal rats for up to 4 days. In one group, reflux of bile and pancreatic juice into the stomach was avoided by previous surgical diversion of the distal common bile duct to the jejunum. DNA synthetic and mitotic activity in the antrum epithelium were estimated by 3H-thymidine pulse labelling and autoradiography during the administration of the peptide. The rate of cell migration was determined in animals killed 1, 2 and 3 days after the 3H-thymidine pulse. Administration of caerulein to normal rats provoked significant increases in both labelling and mitotic indices, and a significant acceleration of the upward cell migration in the glandular tubes. In the animals with distal diversion of bile and pancreatic secretions both labelling and mitotic indices were also increased over control values under the effect of the peptide. These data indicate that administration of caerulein stimulates cell proliferation in the antral gastric mucosa. This effect cannot be explained through increased reflux of pancreaticobiliary secretions in the stomach.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 103
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 699-709 
    ISSN: 1432-0878
    Schlagwort(e): Testis ; Spermatogenic cycle ; Sertoli cell ; Lipid ; Morphometry ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The volume and surface area of lipid inclusions often present in the cytoplasm of rat Sertoli cells was measured directly from semi-thin sections of perfusion-fixed testicular tissues using an image analyser linked to a light microscope. Sertoli cell nuclei were used as a reference for comparing any variations in the measured parameters of lipid inclusions during the rat spermatogenic cycle. Volume density of Sertoli cell lipid inclusions was assessed by morphometric analysis of Sertoli cells photographically reconstructed from electron micrographs. Maximum lipid content in Sertoli cells occurred during stages IX–XIV of the spermatogenic cycle, then declined at stages I–III and remained low from stages IV–VIII. The persistence and increase in number of many large Sertoli cell lipid inclusions beyond the stage where spermatid residual bodies are phagocytosed within the Sertoli cells (stage IX) suggests that the synthesis and lipolysis of Sertoli cell lipid inclusions represents an intrinsic functional cycle of the Sertoli cells. Stage-dependent variations in the lipid content of rat Sertoli cells offers morphological evidence that the metabolic duties of the Sertoli cells are synchronised with the spermatogenic cycle to provide local coordination of the proliferation and maturation of the germ cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 104
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 717-724 
    ISSN: 1432-0878
    Schlagwort(e): Ovary ; Ovarian follicle ; Atresia ; Immunoregulation ; Immune tolerance ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Thy-1+ cells, producing Thy-1+ material, have been demonstrated by the indirect immunoperoxidase technique in the theca of growing ovarian follicles of the rat. OX-2 antigen, known as the minor glycoprotein of rat thymocytes, was detected in granulosa cells of non-growing follicles. Ia+ cells of dendritic type and/or activated macrophages were identified in the granulosa of advanced degenerating follicles, and remnants of the zona pellucida exhibited immunoglobulins. In some ovaries immunoglobulins were also bound to the zona pellucida of oocytes of early degenerating antral follicles. Medium-sized antral follicles with degenerating granulosa were occasionally invaded by cells carrying antigens of cytotoxic T lymphocytes or other T lymphocyte subsets, while degenerating large antral follicles were sometimes invaded by cells exhibiting antigen of cells with natural killer function (but not antigens of T lymphocytes). Granulosa cells of some degenerating antral follicles exhibited class-I antigens derived from the major histocompatibility complex. We suggest that cell-mediated control mechanisms of antigen expression and metabolism of tissue cells during their differentiation and degeneration should be considered in addition to the well-documented hormonal dependence of some tissues.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 105
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 237 (1984), S. 195-202 
    ISSN: 1432-0878
    Schlagwort(e): Pituitary ; Prolactin cells ; Estrogen ; Heterogeneity ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary This study was conducted to determine the functional and/or developmental relationships among three heterogeneous types of prolactin cells (I, II and III) in rats. Rats were injected subcutaneously daily with estradiol or testosterone propionate on days 10–20 after birth. Estradiol increased the proportion of cell types II and III, increased serum PRL levels 12-fold in males and 15-fold in females, and increased pituitary levels of prolactin 12-fold in males and 5-fold in females. Testosterone mainly increased the proportion of the Type-II cells, decreased serum levels of prolactin in males only, and did not change pituitary levels of prolactin. In a second experiment, treatment of rats with nafoxidine for five days after E2 treatment (days 10–20 after birth) increased the proportion of Type-I cells and decreased the proportion of Type-III cells and decreased serum and pituitary levels of prolactin by 50% in females and by 15 and 45% in males. In a third experiment utilizing adult male rats, estradiol and testosterone were found to modulate the relative ratios of the different types of PRL cells as they did in immature animals. The data taken as a whole suggest the possibility of an estrogen-stimulated conversion of one cell type to another, which may be a reflection of prolactin secretory activity.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 106
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 237 (1984), S. 245-252 
    ISSN: 1432-0878
    Schlagwort(e): Pineal organ ; Interstitial cells ; Astrocytes ; Immunocytochemistry ; Rat ; Mouse
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Antigenic markers characteristic of astrocytes and their differentiative states (i.e., glial fibrillary acidic protein (GFAP), vimentin, and M1 and C1 antigens) were investigated in the pineal gland of mouse and rat using double immunolabeling techniques. In both species the socalled interstitial cells as characterized by TEM were shown to be astrocytes, since they expressed vimentin, but neither fibronectin (a marker for fibroblasts and endothelial cells) nor the neuron-specific L1 antigen or tetanus toxin receptors. Subpopulations of vimentin-positive pineal astrocytes were also GFAP- and C1- antigen-positive. M1- antigenpositive cells were not detected. It is concluded that a considerable proportion of interstitial cells in the pineal gland of rat and mouse are immature astrocytes which, in contrast to other parts of the central nervous system, persist into adulthood.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 107
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 237 (1984), S. 427-441 
    ISSN: 1432-0878
    Schlagwort(e): Subcommissural organ ; Reissner's fiber ; Ependyma ; Secretory process ; Comparative analysis ; Immunocytochemistry ; Vertebrates
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The subcommissural organs (SCO) of 76 specimens belonging to 25 vertebrate species (amphibians, reptiles, birds, mammals) were studied by use of the immunoperoxidase procedure. The primary antiserum was obtained by immunizing rabbits with bovine Reissner's fiber (RF) extracted in a medium containing EDTA, DTT and urea. Antiserum against an aqueous extract of RF was also produced. The presence of immunoreactive material in cell processes and endings was regarded as an indication of a possible route of passage. Special attention was paid to the relative development of the ventricular, leptomeningeal and vascular pathways established by immunoreactive structures. The SCO of submammalian species is characterized by (i) a conspicuous leptomeningeal connection established by ependymal cells, (ii) scarce or missing hypendymal cells, and (iii) a population of ependymal cells establishing close spatial contacts with blood vessels. The SCO of most mammalian species displays the following features: (i) ependymal cells lacking immunoreactive long basal processes, (ii) hypendymal secretory cells occurring either in a scattered arrangement or forming clusters, (iii) an occasional leptomeningeal connection provided by hypendymal cells, and (iv) in certain species numerous contacts of secretory cells with blood vessels. In the hedgehog immunoreactive material was missing in the ependymal formation of the SCO, but present in hypendymal cells and in the choroid plexuses. The SCO of several species of New-and Old-World monkeys displayed immunoreactive material, whereas that of anthropoid apes (chimpanzee, orangutan) and man was completely negative with the antisera used.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 108
    ISSN: 1432-0878
    Schlagwort(e): Subcommissural organ ; Ependyma ; Comparative aspects ; Immunocytochemistry ; Secretory process ; Blood vessels
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In 76 specimens (amphibians, reptilians, mammals) belonging to 25 different vertebrate species, the region of the subcommissural organ (SCO) was investigated with the use of a primary antiserum raised against an extract of bovine Reissner's fiber+the immunoperoxidase procedure according to Sternberger et al. (1970). In the SCO of a toad (Bufo arenarum) and several species of reptiles (lacertilians, ophidians, crocodilians), the ependymal cells were the only type of secretory cell displaying vascular contacts, whereas in mammals ependymal and hypendymal cells established intimate spatial contacts with blood vessels. In Bufo arenarum, but especially in the reptilian species examined, the ependymo-vascular relationship was exerted by a population of ependymal cells having a rather constant location within the SCO and projecting to capillaries that showed a remarkably constant pattern of anatomical distribution. In the SCO of mammals the modality and degree of the structural relationships between secretory cells and blood vessels varied greatly from species to species. In the SCO of the armadillo and dog the secretory tissue was organized as a thick, highly vascularized layer with most of the cells oriented toward the capillaries. A rather opposite situation was found in the SCO of New-and Old-World monkeys, where vascular contacts were restricted to a few ependymal cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 109
    ISSN: 1432-0878
    Schlagwort(e): Thyroid gland, fetal ; Cytoskeleton ; Cytocha lasin B ; Vinblastine ; Colchicine ; Follicular development (thyroid) ; Tissue culture ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Thyrotropic hormone (TSH) or cAMP accelerate the formation of follicular cavities in the explanted thyroid gland of the 15-day-old rat fetus. Cytochalasin B or vinblastine and nocodazole or colchicine, which disorganize microfilamental and microtubular structures respectively, inhibit or completely block in vitro-induced folliculogenesis. Exposure of the thyroid tissue to lumicolchicine, a structural isomer of colchicine deprived of antimicrotubular activity, does not inhibit the activation of folliculogenesis induced by TSH. These results are strong evidence for the supposition that microfilaments and microtubules are involved in the TSH-stimulated mechanisms resulting in thyroid folliculogenesis. Folliculogenesis requires the integrity of both microfilaments and microtubules.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 110
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 237 (1984), S. 521-524 
    ISSN: 1432-0878
    Schlagwort(e): α-Melanocyte-stimulating hormone ; α-MSH-like peptide ; Immunocytochemistry ; Hypothalamus ; Lizard (Lacerta muralis)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The distribution of α-melanocyte-stimulating hormone (α-MSH) was studied in the brain of the lizard Lacerta muralis by means of immunocytochemical staining methods. α-MSH-like containing cells were found in the ventro-lateral preoptic area and the paraventricular and supraoptic nuclei. Some scattered cells staining for α-MSH were also detected in the mesencephalo-diencephalic boundary region, while numerous α-MSH-like nerve fibres were localized in the medial eminence. No reaction was observed after the use of antiserum preabsorbed with synthetic antigen. These findings suggest that an α-MSH-like peptidergic system could possibly be involved in the hypothalamo-hypophysial regulation and/or play a role as neurotransmitter in this animal.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 111
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 238 (1984), S. 203-205 
    ISSN: 1432-0878
    Schlagwort(e): Neuropeptide Y ; Hypothalamus, human ; Immunocytochemistry ; Pituitary stalk
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In order to study the distribution of neuropeptide Y-like immunoreactivity in the human hypothalamus, an immunocytochemical localization of this peptide was performed. Using antibodies developed against synthetic porcine neuropeptide Y (NPY), we have been able to localize immunoreactivity in neuronal cell bodies located exclusively in the infundibular nucleus. Immunostained fibers were found in several regions in the hypothalamus with a high concentration in the periventricular areas. Fibers were also found in the neurovascular zone of the median eminence, the pituitary stalk and the posterior pituitary. These results suggest that immunoreactive material related to porcine NPY is present in the human hypothalamus, with a distribution similar to that observed in the rat.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 112
    ISSN: 1432-0878
    Schlagwort(e): Peptidergic neurotransmission ; Lymnaea stagnalis ; Immunocytochemistry ; Ultrastructure
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Three neuronal systems of the pond snail Lymnaea stagnalis were immunocytochemically investigated at the ultrastructural level with the unlabeled peroxidase-antiperoxidase technique. Preliminary electrophysiological and cell-filling investigations have shown that a cluster of neurons which reacts positively with an antiserum against the molluscan cardio-active peptide FMRFamide, sends axons to the penis retractor muscle. In this muscle anti-FMRF-amide (aFM) positive axons form neuro-muscular synapses with (smooth) muscle fibers. The morphological observations suggest the aFM immunoreactive system to be involved in peptidergic neurotransmission. In the right parietal ganglion a large neuron (LYAC) is penetrated by aFM positive axons which form synapse-like structures (SLS) with the LYAC. The assumption that the SLS represent the morphological basis for peptidergic transmission is sustained by the observation that iontophoretical application of synthetic FMRFamide depolarizes the LYAC. The axons of a group of pedal anti-vasopressin (aVP) positive cells run in close vicinity to the cerebral ovulation (neuro-)-hormone producing cell system (CDC system) Synapses or SLS between the two systems were not observed. The fact that (bath) application of arg-vasopressin induces bursting in the CDC, may indicate that the vasopressin-like substance of the aVP cells is released non-synaptically.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 113
    ISSN: 1432-0878
    Schlagwort(e): Somatostatin ; Somatostatin cells ; Rat stomach ; Paracrine action ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Somatostatin cells in the stomach of the rat have a characteristic shape and distribution. In the antral mucosa they occur together with gastrin cells and enterochromaffin cells at the base of the glands. In the oxyntic mucosa they are scattered along the entire glands with some predominance in the zone of parietal cells. Throughout the gastric mucosa the somatostatin cells possess long and slender processes that emerge from the base of the cell and end in clublike swellings. Such processes appear to contact a certain proportion of neighbouring gastrin cells in the antral mucosa and parietal cells in the oxyntic mucosa. Exogenous somatostatin given by intravenous infusion to conscious rats counteracted the release of gastrin stimulated by feeding, elevated antral pH or vagal excitation. Gastrin causes parietal cells to secrete HCl and endocrine cells in the oxyntic mucosa to mobilise and synthesise histamine. Somatostatin is known to block the response of the parietal cells to gastrin. In contrast, somatostatin did not block the response of the histamine-storing endocrine cells to gastrin, perhaps because these endocrine cells lack receptors to somatostatin. Conceivably, somatostatin in the gastric mucosa has a paracrine mode of action. The observations of the present study suggest that somatostatin may affect some, but not all of the various cell types in the stomach. Under physiological conditions this selectivity may be achieved in the following ways: 1) Communication may be based on direct cell-to-cell contact. 2) Only certain cell types are supplied with somatostatin receptors.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 114
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 186 (1978), S. 399-412 
    ISSN: 1432-0878
    Schlagwort(e): Pituitary gland ; Dog ; Pars distalis ; Thyrotropin (TSH) ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Using the immunoperoxidase technique and antisera to the specific beta (β) subunits of bovine and rat TSH1, selective immunocytochemical staining was localized in a specific cell population in the pars distalis of the dog pituitary gland. These TSH cells were found to be positive to aldehyde fuchsin, alcian blue, periodic acid-Schiff (PAS) and aniline blue. With the performic acidalcian blue (pH 0.2) -PAS-orange G procedure these cells stained blue-purple, demonstrating FSH/LH cells (blue or turquoise), ACTH/MSH cells (redpurple) and PRL cells (orange-red). The TSH cells were further differentiated from other functional cell types of the pars distalis on the basis of their typical cytological features, intraglandular distribution and by immunocytochemical double staining. In the pars distalis of adult male dogs the TSH cells were mostly shown to be smaller in size and less numerous than in bitches in the anestrous phase of the sexual cycle. Moreover, cytological alterations in the immunoreactive thyrotrophs in the pituitary of male and female dogs generally paralleled the spontaneous changes in thyroid function associated with thyroid atrophy and/or pituitary insufficiency, and thyroid hyperplasia or goiter. In conclusion, because of their specificity and high potency, the antisera to the β-subunits of bovine and rat TSH represent an effective tool for the selective immunocytochemical localization of TSH in the dog pituitary. This allows the study of the morphology and function of TSH cells under different physiological, pathological and experimental conditions.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 115
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 238 (1984), S. 497-502 
    ISSN: 1432-0878
    Schlagwort(e): D2 glycoprotein ; Adrenal gland ; Immunocytochemistry ; Ultrastructure ; Cell adhesion
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The ultrastructural localization of the glycoprotein D2 in rat adrenal gland was investigated using immunohistochemical methods, and D2 localization in cultures of adult bovine chromaffin cells was studied by immunofluorescence. D2 was found to be situated on nerve fibers passing through the adrenal cortex and in the medulla zone, and also on the surface of all chromaffin cells. In addition, it was strongly expressed on the surface of glial (Schwann) cells. Cortical cells were unreactive to the antiserum. In cultures, all adrenalin and noradrenalin [dopamine-β-hydroxylase (DBH)-positive] cells were surface labelled for D2. A less frequent second cell type was recognized in vitro which was DBH negative but D2 positive. Such cells were presumed to be Schwann cells. These data are discussed in terms of the developmental origin of the cells and with regard to the putative functional rôle of D2 in cell adhesion phenomena.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 116
    ISSN: 1432-0878
    Schlagwort(e): CRF-neurons ; Hypothalamus ; Development, ontogenetic ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Appearance of immunoreactive corticotropin-releasing factor (CRF)-containing neurons was studied in developing hypothalamus of the rat by use of antisera against rat- and ovine CRF. These neurons were first recognized in the lateral and paraventricular nuclei on days 15.5 and 16.5 of gestation, respectively, when antiserum against rat CRF was employed. Antiserum against ovine CRF revealed the cells two days later exclusively in the latter nucleus. In both nuclei, the neurons increased in number with development. The neurons in the paraventricular nucleus appeared to project their immunoreactive processes to the median eminence via the periventricular and lateral pathways. In the median eminence, the immunoreaction with antiserum to rat CRF was first recognized in its anterior portion in the form of dots on day 16.5 of gestation but as beaded fibers in the external layer on day 17.5; these structures increased in amount with development in rostro-caudal direction. Although antiserum to ovine CRF was less potent in immunostainability than antiserum to rat CRF, it also revealed the beaded fibers in the median eminence on day 17.5 of gestation. Since evidence is available that the paraventricular nucleus is involved in corticotropin release, it is concluded that, in rats, the hypothalamic regulatory mechanism controlling the release of corticotropin initially appears on days 16.5–17.5 of gestation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 117
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 188 (1978), S. 99-106 
    ISSN: 1432-0878
    Schlagwort(e): LHRH-neurosecretion ; Avian hypothalamus ; Vasotocin neurosecretion ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary A fluorescent technique applying specific LHRH and vasotocin antisera was used for the immunocytochemical localization of the respective neurosecretory systems in the hypothalamus of gonadectomized, testosteronetreated and/or serotonin injected male domestic ducks. An immunoreactive (IR) LHRH-producing system, with perikarya located in the preoptic nucleus, could be traced through the ventral hypothalamus down to the external layer of the rostral and caudal ME, in close vicinity to the hypophysial portal system. An IR-vasotocin system originating in the paraventricular and supraoptic nuclei ran through the ventral hypothalamus, but terminated in (i) the external layer of the rostral ME, and (ii) in the posterior lobe of the hypophysis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 118
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 188 (1978), S. 119-132 
    ISSN: 1432-0878
    Schlagwort(e): Neurophysin ; Paraventricular nucleus ; Supraoptic nucleus ; Sheep ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary An antiserum cross-reactive against ovine neurophysins-I-II and -III has been used in conjunction with the immunoperoxidase histochemical procedure to localize the cells of the sheep paraventricular (PVN) and supraoptic nuclei (SON). In order to describe the topographical distribution of the SON and PVN a study was made on the serial sections cut (a) transversely from rostral to caudal positions and (b) sagittally from lateral to medial positions of the hypothalamus. The cells of the SON, when examined in the transverse aspect, extended approximately 1900 μ caudally and when examined in the sagittal plane were contained within a lateral-medial distance of 4830 μ. In each case the SON cells lay adjacent to the optic chiasm. As sections were cut transversely, the cells of the PVN first appeared in a rostral position defined as 0 μ and close to the ventral lining of the third ventricle. This general ventral and ventro-lateral distribution of cells maintained up to a caudal distance of approximately 840 μ. From positions 1260–2310 μ there was a dramatic dorsal shift of the PVN cells which by this time had also extended laterally. The total rostral-caudal distance occupied by the PVN cells was 3150 μ. That the lateral-medial distance occupied by the PVN was small (1050 μ) was determined on examining the magnocellular nuclei in sagittal section.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 119
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 189 (1978), S. 155-166 
    ISSN: 1432-0878
    Schlagwort(e): Levator ani muscle ; Rat ; Neuromuscular junction ; Castration ; Testosterone effect
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The ultrastructure of the neuromuscular junction (n.m.j.) of the androgen-sensitive levator ani muscle was studied in normal adult male rats, in 8-month-old rats castrated at the age of one month and in castrated rats treated with testosterone propionate (TP). Castration does not result in significant changes of the n.m.j. The density of synaptic vesicles and the postsynaptic junctional folds remain practically normal in spite of marked atrophy of the muscle. TP administration for 7 days results in marked changes in preand postsynaptic structures. There is slow progressive depletion of synaptic vesicles, appearance of cisternae and coated vesicles in axon terminals, and coalescence of coated vesicles with the plasma membrane. Coated vesicles are also found inside Schwann cells and among junctional folds. Dense core vesicles appear both in the axon terminals and in the postsynaptic area. Collateral sprouting of terminal axons with the formation of new immature junctions is observed. After 35 days of TP administration depletion of synaptic vesicles continues. Glycogen β-particles, mostly freely dispersed, occasionally seen in axon terminals 7 days after TP administration, subsequently increase in number. In the endplate zone of the muscle fibre increased protein synthesis is indicated by a rapid increase in ribosomes and irregularly located myofilaments and myofibrils. The appearance of n.m.j. after testosterone administration resembles that described after nerve stimulation; the degree of change is however less pronounced.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 120
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 215 (1981), S. 625-633 
    ISSN: 1432-0878
    Schlagwort(e): Teleost ; Pars intermedia ; Immunocytochemistry ; PAP-technique ; MSH ; ACTH ; Endorphin
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The pars intermedia of S. mossambicus contains two different endocrine-cell types. The predominant cell type is lead-haematoxyline-positive and assumed to synthesize MSH and related peptides. The second cell type is PAS positive and its function and product(s) are unknown. Staining of light-microscopic and ultrathin sections with antisera against α-MSH, ACTH 1–24 and human β-endorphin revealed that only the lead-haematoxyline-positive cells of the pars intermedia react with these antisera, and that the secretory granules of these cells contain compounds that were immunoreactive to all three antisera. These findings are in line with the hypothesis that α-MSH, ACTH and endorphins are derived from the same precursor molecule. No specific reaction with one of the antisera could be detected in the PAS positive cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 121
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 189 (1978), S. 277-286 
    ISSN: 1432-0878
    Schlagwort(e): Maternal adrenalectomy ; Rat ; Influence on the adrenals of newborn animals ; Electron microscopy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Maternal adrenalectomy at 7 or 14 days of gestation produced increased cell necrosis within zona reticularis cells on the day of birth and at 24 or 48 h after birth. Small remnants or large portions of adrenocortical cells were present within macrophages. In otherwise normal adrenocortical cells, lipid droplets were incorporated within some mitochondria. Autophagocytosis of single mitochondria was observed within adrenocortical cells. Undoubtedly ultrastructural changes represent stimulation of adrenocortical cells in neonatal rats in response to maternal adrenalectomy.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 122
    ISSN: 1432-0878
    Schlagwort(e): Oxytocin ; Paraventricular nucleus ; Supraoptic nucleus ; Anterior commissural nucleus ; Immunohistology ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The effect of water deprivation or estrogen treatment on the oxytocin content of rat hypothalamic cells was examined using a quantitative immunohistological technique. Oxytocin-containing cells were visualized using the immunoperoxidase technique of Sternberger and a primary antiserum directed against oxytocin. The optical density of the darkest 3.2 μm diameter spot in the cytoplasm of a cell was used as a measure of the oxytocin content of that cell. Water deprivation produced a significant decrease in anti-oxytocin staining in the anterior commissural nucleus of males and females. There was a similar decrease in the paraventricular nucleus of males, but not in the paraventricular nucleus of females or the supraoptic nucleus of either males or females. Estrogen treatment of ovariectomized female rats produced a fall in anti-oxytocin staining in the anterior commissural, but not paraventricular or supraoptic nuclei.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 123
    ISSN: 1432-0878
    Schlagwort(e): Digestive tract ; Fish ; Gastrin-immunoreactive cells ; Pancreatic polypeptide-immunoreactive cells ; Somatostatin-immunoreactive cells ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Gastrin, pancreatic polypeptide and somatostatin immunoreactive cells in the gut of two fish with stomachs (perch and catfish) and a stomachless fish (carp) were studied by immunocytochemistry. In the gastric mucosa of perch and catfish, cells showing gastrin and somatostatin-like immunoreactivity are found, scattered among the surface mucous cells and mucous neck cells. No pancreatic polypeptide (P.P.) immunoreactive cells are detected in the gastric mucosa. Cells showing gastrin and P.P.-like immunoreactivity are observed in the intestinal mucosa of perch, catfish and carp. In this location no somatostatin immunoreactive cells are found.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 124
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 191 (1978), S. 501-506 
    ISSN: 1432-0878
    Schlagwort(e): Neurohypophysis ; Ultrastructure ; Perivascular space ; Hormonerelease ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Neural lobes from rats subjected to neurohypophysial hormone-releasing stimuli were examined electron microscopically following fixation in 4 % tannic acid in 2.5 % glutaraldehyde. This fixation allowed the delineation of the perivascular space in the neural lobe tissue. Measurement of the area of the perivascular space showed that it was significantly increased in the rats subjected to vagal stimulation and intraarterial calcium ions compared to the control rats. The rats which had been subjected to haemorrhage as a hormonereleasing stimulus did not show any significant change in the area of the perivascular space. The significance of these findings in relation to hormone release is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 125
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 191 (1978), S. 507-512 
    ISSN: 1432-0878
    Schlagwort(e): Odontoblasts ; Osteoblasts ; Cementoblasts ; Intercellular attachments ; Electron microscopy (SEM/TEM) ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Osteoblasts of the young rat cranium, and cementoblasts and odontoblasts of young rat molars were prepared by ethanol freeze-fracture prior to critical point drying for scanning electron microscopy (SEM) as well as conventional transmission electron microscopy (TEM) techniques. Critical point drying causes shrinkage which separates the lateral intercellular contacts between neighbours in the same sheet in the case of cementoblasts and osteoblasts, but not those between odontoblasts. These differences are considered to be of functional significance and need to be taken into consideration when formulating theories of calcium influx into the mineralizable matrix of the respective tissues.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 126
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 191 (1978), S. 513-523 
    ISSN: 1432-0878
    Schlagwort(e): Median eminence ; Rat ; Freeze-fracture
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Nerve terminals in the palisade zone of the rat median eminence were investigated with freeze-fracture electron microscopy. Fracture face P of the specific terminals showed two populations of intramembranous particles (IMP): a large and a small variety. The large IMP-s often formed small irregular clusters. In nerve terminals the total number of both populations of IMP-s was considerably less than that found on P membrane faces of ependymal feet. On fracture face E of the nerve terminals, the number of IMP-s was about a quarter of that seen on fracture face P. On both fracture faces of most terminals a few small round impressions (or elevations respectively) were found which may be interpreted as broken necks of either exo- or endocytotic vesicles. Neither gap nor tight junctions occurred at lateral membranes of the specific axon terminals. Similarly, no membrane specializations were observed with freeze-fracturing on membrane areas adjacent to the basement membrane. The findings are discussed in relation to a possible exocytosis mechanism of the hypothalamic releasing and inhibiting hormones.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 127
    ISSN: 1432-0878
    Schlagwort(e): Taste buds ; Circumvallate papillae ; Colchicine ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary It is believed that differentiation and maintenance of taste buds in vertebrates is dependent on the trophic function of their sensory nerve supply. In the present work colchicine was injected into the circumvallate papilla of the rat. This produced a reversible blockade of neuroplasmic transport and disappearance of taste buds. Colchicine inhibited the further differentiation of bud cells, but apparently did not change the life cycle of the cells present already at the time of injection. It is speculated that the neurotrophic factors in this particular cell system are effective to induce cell differentiation only.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 128
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 205 (1980), S. 11-17 
    ISSN: 1432-0878
    Schlagwort(e): Pineal organ ; Subcommissural organ ; Vasopressin ; Oxytocin ; Vasotocin ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Vasopressin and oxytocin were specifically demonstrated in the rat brain using the unlabelled antibody-enzyme method and purification of the first antiserum. Vasopressin and oxytocin fibres extend via the subcommissural organ or habenular commissure into the pineal stalk and terminate in the anterior part of the pineal organ. In addition, immediately adjacent to the subsommissural organ many vasopressin-containing fibres run caudally toward the central grey. These results are discussed in relation to the proposed presence of vasotocin in the pineal gland.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 129
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 205 (1980), S. 43-53 
    ISSN: 1432-0878
    Schlagwort(e): Brain ; Rana temporaria ; Somatostatin-containing neurons ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The brain of the frog Rana temporaria was studied at the light microscopic level with the use of a double immunocytochemical staining method. The telencephalon, diencephalon and rhombencephalon contain somatostatin perikarya and fibers. In the telencephalon, the location of the somatostatin neurons largely corresponds to that of mammals. In the hypothalamus, the somatostatin perikarya are located in and near the magnocellular preoptic nucleus and also in the pars ventralis of the tuber cinereum. Like the somatostatin neurons of the rat hypothalamus, they form a separate subpopulation, different from the neurons producing neurohypophysial hormones. In Rana, somatostatin neurons are also present in (as well as in the vicinity of) the subfornical organ, in the thalamus, the tectum opticum, the interpeduncular nucleus and the caudal end of the roof of the calamus scriptorius. A precise localization of the perikarya of most somatostatin fibers, including those found in the median eminence and the neural lobe, was not attained.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 130
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 210 (1980), S. 167-170 
    ISSN: 1432-0878
    Schlagwort(e): Neuropeptides ; VIP-immunoreactive neurons ; Retina ; Amacrine cells ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Immunoreactive vasoactive intestinal polypeptide (VIP) was detected in a population of amacrine cells in the retina of the rat. Processes of these cells reach both the inner and outer half of the inner plexiform layer where they form sublayers. The VIP neurons are different from previously known amacrine cell types.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 131
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 210 (1980), S. 181-189 
    ISSN: 1432-0878
    Schlagwort(e): Catecholamines ; Neurophysin ; Simultaneous demonstration ; Functional interaction ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary A method was developed that allows the analysis of neuropeptides and monoamines in a single tissue section by the application of the unlabeled antibody method for peptide staining to tissue sections freeze-dried for formaldehyde-induced monoamine histofluorescence. The hypothalamic magnocellular system of male albino rats served as a model for this study; neurons were stained with anti-neurophysin sera, which mark the vasopressin- and oxytocin-associated proteins. Neurophysin-containing perikarya appeared to be surrounded by catecholamine-containing varicosities. This phenomenon was seen to varying degrees within the supraoptic and paraventricular nuclei. The juxtaposition of varicosities and peptidergic neurons suggests an afferent fiber-target neuron relationship that might favor a functional interaction between monoamines and neuropeptides.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 132
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 211 (1980), S. 73-82 
    ISSN: 1432-0878
    Schlagwort(e): Preputial glands ; Nude mice ; Ultrastructure ; Gas chromatography
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The preputial glands of male nude (nu/nu) mice were analyzed by a combination of electron microscopy and gas chromatography to determine whether or not they are affected, like developing hairs and nails, by the nu/nu genotype. Results of the analyses revealed no differences between the glands of nude and normal male mice in either their ultrastructural characteristics or lipid secretory products.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 133
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 211 (1980), S. 105-115 
    ISSN: 1432-0878
    Schlagwort(e): Rat ; Preovulatory follicle ; Ultrastructure ; Degeneration ; Atresia
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary To identify and describe ovarian follicles committed to undergo follicular degeneration (atresia), immature rats were primed with pregnant mare serum gonadotropin (PMSG). After PMSG treatment, preovulatory follicles develop but subsequently degenerate. Prior to the appearance of pyknotic nuclei (Stage I of atresia), degenerative changes were observed in focal areas of the granulosa cell layer. These changes include “blebbing” of the cytoplasm and alterations in the shape of the granulosa cells. The appearance of these degenerative changes coincides with a decrease in ovarian concentrations of estradiol and testosterone. Since estrogens and androgens maintain the follicle, the decline in estradiol and testosterone could be responsible for the further degenerative alterations that lead to complete deterioration of the preovulatory follicle. In Stage I atretic follicles, lysosome-derived autophagic vacuoles develop and macrophages invade both the thecal and granulosa cell layers. The combined actions of the autophagic vacuoles and macrophages could destroy both the granulosa-cell and thecal layers and thereby transform the preovulatory follicle into an ovarian cyst.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 134
    ISSN: 1432-0878
    Schlagwort(e): Lymph node ; Macrophages ; Postcapillary high endothelial venules ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The afferent lymphatic vessels of rat popliteal lymph nodes were interrupted, and the histological alterations in the lymph nodes occurring 1 to 14 weeks after operation were studied. One week after operation the number of macrophages was considerably reduced and continued to decrease during the subsequent time periods studied. A 6 weeks most macrophages had disappeared. Simultaneously the immunological activity diminished and had completely disappeared 8 weeks after operation. Three weeks after operation the endothelial cells of the postcapillary high endothelial venules had flattened, and the number of immigrating lymphocytes was greatly reduced. Subsequently the lymph nodes became depleted of both macrophages and lymphocytes, leaving only the reticuloendothelial framework.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 135
    ISSN: 1432-0878
    Schlagwort(e): α- and β-Endorphins ; Met-enkephalin ; Brain ; Immunocytochemistry ; Rana temporaria (Amphibia, Anura)
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In the brain of Rana temporaria, two distinct systems reactive with α- and β-endorphin antisera, respectively, and with a met-enkephalin antiserum, have been detected immunohistochemically. Neurons reacting with α- and β-endorphin antisera are located (1) in the preoptic nucleus, and (2) in the pars ventralis of the tuber cinereum. Immunoreactive nerve fibres of both groups of perikarya end in the infundibular floor near the capillaries and the preoptico-hypophysial tract. Control reactions have shown that the immunoreactivity is suppressed by the corresponding antigens, but also by β-LPH. In view of these results the immunoreactive systems examined correspond to an α/β-endorphin system or a lipotropinergic system. Neurons reacting with the met-enkephalin antiserum are located in the paraventricular organ. Intense immunofluorescence was observed in the infundibular floor. Controls show that the labelling by met-enkephalin antiserum is exclusively suppressed by met-enkephalin. In the pituitary gland, on the other hand, α- and β-endorphin antisera reveal: 1) the MSH/ACTH-like cells of the pars intermedia and 2) the ACTH-like cells of the pars distalis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 136
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 234 (1983), S. 427-437 
    ISSN: 1432-0878
    Schlagwort(e): Corticotropes ; Rat fetus ; Ultrastructure ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Corticotropes of rat fetuses aged 16, 18 and 21 days were localized by the indirect antibody-enzyme method on semithin sections of the pituitary. The development of the ultrastructure of these cells was observed on consecutive ultrathin sections. In comparison with previous data our present results show that identification of a fetal cell type cannot be based entirely on morphological criteria. The structural peculiarities of corticotropes obtained from studies in vivo are compared with those observed in cells maintained in vitro.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 137
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 234 (1983), S. 439-450 
    ISSN: 1432-0878
    Schlagwort(e): Avidin ; Avidin-biotin interaction ; Biotin affinity histochemistry ; Biotin hydrazide ; Immunocytochemistry ; Magnum gland ; Secretion ; Oviduct
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The location of endogenous avidin was studied cytochemically in the magnum tissue of the oviduct of laying hens. Two methods, based on an interaction of avidin-biotin with biotin hydrazide-peroxidase (B-HRP) as an affinity reagent, and on an immunoperoxidase technique, were tested by morphological analysis. The data obtained by both methods showed that in the magnum B-HRP is a strictly substitutive reagent for endogenous avidin. Avidin was clearly demonstrated in large amounts in the secretory granules of some epithelial cells and tubular gland cells, but was absent from mucous cells, the goblet cells, which had been believed to be the location of avidin production, and from ciliated cells. These granules had previously been demonstrated by both electron-microscopic cytochemical techniques. Especially in acinar cells, they were nonhomogeneous with a speckled core and a dense peripheral part. They ranged in size from 500 to 2200nm in diameter in the gland and 180 to 720 nm in the epithelium. Columnar epithelial cells containing avidin granules had a strong resemblance to those of the protodifferentiated tubular gland cells in the magnum of chicks pretreated with daily estrogen or estrogen plus progesterone, and might have migrated towards the acinus as substitutional secretory cells. Therefore, the acinar cells of the magnum, considered to be composed of several secretory protein-producing systems, are dependent on estrogen and/or progesterone in the oviduct of the laying hen.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 138
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 234 (1983), S. 547-559 
    ISSN: 1432-0878
    Schlagwort(e): Myelin proteolipids ; Oligodendrocytes ; Golgi apparatus ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Purified antibodies directed against myelin proteolipids were isolated by affinity chromatography of whole serum obtained from rabbits inoculated with myelin. These antibodies were specific for light, medium and dark oligodendrocytes. Astrocytes, neurons and their processes were not reactive. Immunocytochemical investigations showed that the membranes of the Golgi complex are highly labeled by these antibodies. Diffuse cytoplasmic labeling was only observed on the light and medium oligodendrocytes and was absent from the dark types. Vesicles possessing a punctate staining were detected in the vicinity of the Golgi complex and the oligodendroglial membrane. A discontinuous labeling of the plasmalemma appears to be characteristic of the actively myelinating light and medium oligodendrocytes. In compact myelin sheaths positive immunostaining was only detected at the dense line. The immunocytochemical localization of the myelin proteolipids in the oligodendrocytes is in accordance with previously published biochemical data.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 139
    ISSN: 1432-0878
    Schlagwort(e): Adrenalectomy ; Hypophysectomy ; Compensatory adrenal growth ; Rat ; Stereology
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Compensatory hypertrophy of the remaining gland in unilaterally adrenalectomized rats was investigated by morphometric techniques. It was observed that compensatory adrenal growth occurred in both dexamethasone-treated and hypophysectomized rats, receiving maintenance doses of ACTH. However, it was only half that found in intact animals. These results support the view that activation of the hypothalamo-hypophyseal axis is not the unique mechanism underlying adrenal compensatory hypertrophy in the rat.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 140
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 211-214 
    ISSN: 1432-0878
    Schlagwort(e): Adenohypophysis ; Pars distalis ; Immunocytochemistry ; Amphibia ; Gymnophiona
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The indirect immunofluorescence method was used to identify and locate LTH-, STH-, LH-, TSH-, ACTH- and MSH-immunoreactive cells in the pituitary of Typhlonectes compressicaudus (Gymnophiona). The present study defines the histological and histochemical staining properties of each cell type identified.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 141
    ISSN: 1432-0878
    Schlagwort(e): Caldesmon ; Actin ; Immunocytochemistry ; Small intestine ; Smooth muscle ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The distribution of caldesmon (a calmodulin-binding, F-actin-interacting protein) (Sobue et al. 1982) and of actin was studied in the rat's small intestine by means of light-microscopic immunocytochemistry. Positive immunostaining for caldesmon was seen in smooth muscle cells of the intestinal wall, and of blood vessels, and in the apical portion of the absorptive epithelial cells. The immunoreactivity in goblet cells was difficult to recognize. The positive reaction to immunostaining for actin showed almost the same pattern as that for caldesmon. These results suggest that this calmodulin-binding protein may play an important role in the control of actin-myosin interaction in smooth muscle cells and in non-muscle cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 142
    ISSN: 1432-0878
    Schlagwort(e): FMRFamide ; Bovine pancreatic polypeptide ; Immunocytochemistry ; Peptidergic neurons ; Leptinotarsa decemlineata
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Particular neurons in the nervous system of the Colorado potato beetle, Leptinotarsa decemlineata, are recognized by antisera against bovine pancreatic polypeptide and FMRFamide. Both antisera react with the same neurons. Solid phase absorptions showed that antiserum against bovine pancreatic polypeptide cross-reacts with FMRFamide, whereas antiserum against FMRFamide cross-reacts with bovine pancreatic polypeptide. Some of the immunoreactive neurons have axons branching extensively within the neuropile, which suggests that the peptide is used as transmitter. In the corpus cardiacum, a neurohaemal organ in insects, numerous immunoreactive axon terminals are present. Here, the peptide material is presumably released as a hormone.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 143
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 433-438 
    ISSN: 1432-0878
    Schlagwort(e): Mammary gland ; Ferritin-concanavalin A ; Concanavalin A ; Endocytosis ; Membrane reuse ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Ferritin-concanavalin A (Fer-Con A) was used to label the apical plasma membrane of the lactating cell to determine whether membrane internalization takes place. Rat glands were infused in vivo via the teat with 0.2 mg of Fer-Con A in 0.2 ml tris buffer (pH 7.0) containing 0.1% trypan blue, the latter acting as a marker of the infusate. Tissues were obtained from separate animals 5, 10 and 60 min postinfusion. Fer-Con A was seen in alveolar lumina bound to the outer surfaces of apical plasma membrane, microvilli and milk fat globules. It was observed within lactating cells on the inner membrane surfaces of endocytotic vesicles, Golgi cisternae, and secretory vesicles containing casein micelles, and in multivesicular bodies and lysosomes. Internalization of the ferritin-lectin conjugate into casein-containing secretory vesicles was detectable in the 5-min postinfusion tissue. Lysosomes were the only structures in control tissue that contained particles bearing some resemblance to Fer-Con A. The data provide evidence that apical plasma membrane is internalized and distributed to a number of intracellular compartments.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 144
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 449-452 
    ISSN: 1432-0878
    Schlagwort(e): Suprachiasmatic nucleus ; Morphometry ; Synapses ; Sexual dimorphism ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The suprachiasmatic nucleus (SCN) of male rats was estimated to contain 16×106 synaptic appositions (unilaterally) or 250×106 appositions in 1 mm3 tissue of the nucleus with an average of 1404 appositions per neuron. There are significantly fewer synaptic appositions in the suprachiasmatic nucleus of female rats (15×106 per SCN or 236×106 in 1 mm3 tissue of SCN with 1264 appositions per neuron on an average). Additionally, numbers of various types of synapses (axo-somatic, invaginated, dendrodendritic and optic) are estimated.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 145
    ISSN: 1432-0878
    Schlagwort(e): Monosodium-1-glutamate ; Neuropathology ; Rat ; Superior colliculus ; Toxicology
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Systemic administration of monosodium-1-gluta-mate by single injections of 4 mg/g body weight in infant rats (2–10 days of age) results in acute swelling of cytoplasm and nuclear pyknosis of neurons in the stratum zonale and stratum griseum superficiale of the superior colliculus. Multiple daily doses of 4 mg/g body weight monosodium-1-glutamate result in an almost complete loss of neurons in these two superficial layers. The deeper layers appear not to be affected. No pathological effects were observed in the lateral geniculate body or pretectal complex. Light-and electron-microscopic studies reveal that the optic nerves are remarkably shrunken and many myelinated as well as unmyelinated axons are lost. Injection of 3Hproline into the vitreous body of one eye results in limited transport to the suprachiasmatic nucleus, lateral geniculate body and to lateral portions of the superior colliculus. The small percentage of intact axons in the optic nerve, as well as the limited proline transport from the eye, suggest that administration of monosodium-1-glutamate leaves intact some optic fibers, a portion of which belongs to the retinohypothalamic tract.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 146
    ISSN: 1432-0878
    Schlagwort(e): Exocrine pancreas ; Calcium pool ; Calcium release ; Electron microscopy ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In an attempt to identify a cellular Ca2+-pool, from which calcium is released when secretagogues are applied, tissue fragments of the rat exocrine pancreas were incubated and fixed with glutaraldehyde in the presence of calcium. By means of this procedure electron-dense deposits were found on plasma membranes. X-ray microanalysis showed that these deposits contain calcium. Stimulation of tissue fragments with the use of the secretagogues carbachol or cholecystokinin reduced the number of deposits by about 80%. When the antagonist atropine was applied after carbachol stimulation, deposits reappeared on cell membranes, which then disappeared again after a second stimulation with cholecystokinin. In the presence of procaine, carbachol was inhibited and only slightly reduced the Ca2+-deposits on the plasma membranes. These results suggest that a calcium pool, from which calcium is released to induce enzyme secretion on stimulation, is located in the cell membrane
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 147
    ISSN: 1432-0878
    Schlagwort(e): Somatostatin ; Ontogenesis ; Electron-microscopic immunohistochemistry ; Median eminence ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The development of immunoreactive (ir) somatostatin-containing nerve terminals in the rat median eminence (ME) has been examined electron-microscopically. Nerve fibers containing ir particles scattered throughout the axoplasm are first seen in the external layer of the ME on day 18.5 of gestation, and, on day 21.5 appear to terminate on the basement membrane of the perivascular space of the portal vessels. After birth, the fiber terminals contain several membrane-limited granules, which are labeled with ir PAP particles. Ultrathin, Epon-embedded sections of ME, treated by the protein A gold-labeling method for somatostatin, demonstrate positively labeled granules in the nerve fibers in the postnatal ME, but in the prenatal tissue, no specific gold-labeling is found. These findings show that, in the external layer of the ME, somatostatin storing occurs in the granules in the axonal terminals after birth.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 148
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 199 (1979), S. 271-279 
    ISSN: 1432-0878
    Schlagwort(e): Subsurface cisterns ; Neurons ; Paraventricular nucleus ; Hypothalamus ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Structures identified as subsurface cisterns (SSC's) were found in neurons of the paraventricular nuclei of the rat hypothalamus. They appeared as cytoplasmic organelles consisting most often of stacks of parallel cisterns apposed to the neuronal plasmalemma. These SSC's were located in the interneurons of the parvocellular system, but not in neurosecretory cells and glial cells. SSC's were seen at zones of cytoplasm apposed to neuronal or glial cell processes, showing in some instances specific relationships with synaptic areas. The morphological features of these SSC's are described, and their possible functional significance is briefly discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 149
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 491-493 
    ISSN: 1432-0878
    Schlagwort(e): Brain vessels ; Basal lamina ; Pericytes ; Endothelial cells ; Glial cells ; Argyrophilic staining ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Vibratome sections obtained from perfusion-fixed rat brains were stained by means of silver impregnation and physical development according to Gailyas (1970). Small pieces of the cerebral cortex were postfixed with buffered osmium tetroxide solution and processed for electron microscopy to examine the localization of the silver deposit at the cellular level. The cell surfaces of pericytes and smooth muscle cells were completely outlined by silver grains. Endothelial cells and perivascular astrocytes, however, showed an asymmetric distribution of the silver deposit, i.e., the deposit was restricted to the abluminal endothelial surface and to the astrocytic membrane adjacent to the vessel wall, respectively. The method allowed a clear-cut distinction between perikarya of endothelial cells and pericytes as well as glial cells in perivascular position, even at the light-microscopic level.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 150
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 245-248 
    ISSN: 1432-0878
    Schlagwort(e): Corticotropin-releasing factor ; Immunocytochemistry ; Hypothalamus ; Domestic fowl
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The corticotropin-releasing factor (CRF)-containing neurons were investigated in the brain of the domestic fowl by means of the peroxidase-antiperoxidase technique at the light-microscopic level. The detection of CRF-immunoreactivity was facilitated by silver intensification. CRF-containing perikarya were found in the paraventricular, preoptic and mammillary nuclei of the hypothalamus and in some extrahypothalamic areas (nuclei dorsomedialis and dorsolateralis thalami, nucleus accumbens septi, lobus parolfactorius, periaqueductal gray of the mesencephalon, nucleus oculomotorius ventralis). Immunoreactive nerve fibers and terminals were demonstrated in the external zone of the median eminence and the organum vasculosum of the lamina terminalis. These results indicate that an immunologically demonstrable CRF-neurosecretory system also exists in the avian central nervous system.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 151
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 249-255 
    ISSN: 1432-0878
    Schlagwort(e): Oocyte ; Nucleolus ; Silver staining ; Electron microscopy ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The nucleoli of dictyate-stage growing oocytes in rat ovaries were examined both with routine electron microscopy and electron microscopy after silver nitrate and ammoniacal silver nitrate (Ag-AS) staining. The nucleoli of the unilaminar follicular oocytes consist of twisted strands of dense fibrillar components, aggregates of granular components, and small fibrillar centers. After Ag-AS staining, silver grains are numerous on the dense fibrillar strands, fewer on the fibrillar centers, and very sporadic on the granular aggregates. The same stainability of three nucleolar components with the Ag-AS method was also confirmed in the nucleoli segregated by actinomycin D. During the transition of growing oocytes from bilaminar to plurilaminar follicle stage, the nucleolar dense fibrillar strands gradually conglomerate and are transformed into large and compact spherules. The stainability of dense fibrillar components with the Ag-AS method was lost along with this nucleolar transformation. These results may provide some new clues on the functional significance of AgAS-positive proteins in the nucleoli.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 152
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 237 (1984), S. 103-109 
    ISSN: 1432-0878
    Schlagwort(e): Synapses ; Synaptogenesis ; Development fetal ; Olfactory cortex ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Electron microscopy was used to study synaptogenesis in prepyriform cortex of fetal rat pups during early stages of synapse formation. Of special interest is the frequent occurrence of unapposed, developing synaptic specializations in axon and growth cone profiles. The location and morphology of the unapposed specializations suggests that thay are presynaptic in nature. These presumably immature presynaptic specializations are found in the lateral olfactory tract and subjacent cortex. Intermediate forms between uncontacted presynaptic specializations and definitive synapses suggest a synaptogenic sequence in which initial development of an immature presynaptic specialization begins without apposition of a postsynaptic element at that location. This implies that initiation of presynaptic development is not dependent upon postsynaptic contact and also raises the question of whether synaptic contacts could be established via presynaptic induction of postsynaptic formation.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 153
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 237 (1984), S. 185-186 
    ISSN: 1432-0878
    Schlagwort(e): Gap junction ; Cytoskeleton ; Heart ; Ultrarapid freezing ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Using ultrarapid-freezing techniques and freezefracture electron microscopy, we report here a close association between cardiac gap junctions and specialized membrane domains containing regularly-spaced furrows. These specialized furrowed domains are observed only during periods of gap junction re-organisation (i.e., connexon redistribution) and may reflect the presence of underlying cytoskeletal elements controlling the position of connexons in the membrane.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 154
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 237 (1984), S. 371-373 
    ISSN: 1432-0878
    Schlagwort(e): Endothelium ; Transport, intracellular ; Transport vesicles, channels ; Micropinocytosis ; Capillaries ; Endometrium ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Three types of transendothelial channels are described in the endothelium of blood capillaries in the endometrium of the rat. It is postulated that they may function as pores draining interstitial fluid to the venous blood.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 155
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 237 (1984), S. 375-377 
    ISSN: 1432-0878
    Schlagwort(e): Thyroid ; Immunocytochemistry ; Caldesmon ; Actin ; Endocytosis ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The distribution of caldesmon (a calmodulin-binding, F-actin interacting protein; Sobue et al. 1982) and actin was studied in the rat thyroid gland by means of light-microscopic immunocytochemistry, and the fine-structural distribution of actin filaments was examined by use of heavy meromyosin (HMM). Caldesmon and actin were demonstrated in the apical cytoplasm of almost all the follicle epithelial cells in normal as well as TSH-treated animals. Immunoreactivities for both caldesmon and actin showed almost the same pattern in localization. The smooth muscle cells of the blood vessels were also positive for caldesmon and actin. By electron microscopy, numerous actin filaments decorated by HMM and running perpendicularly or randomly to the apical surface were recognized in the apical cytoplasm of the follicle epithelial cell. These results suggest that caldesmon and actin, in conjugation with calmodulin, play a role in the regulation of cellular activity such as exocytosis and endocytosis in the apical portion of the follicle epithelial cell.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 156
    ISSN: 1432-0878
    Schlagwort(e): Hypothalamo-hypophysial system ; Rat ; Tanycytes ; Ontogeny
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The differentiation of tanycytes was studied light and electron microscopically during the perinatal period in rats, the time when functional connections between hypothalamus and hypophysis are established. The 3rd ventricle is slit-like between 16 and 18 days of the prenatal period. Its wall is formed by intensively proliferating matrix cells with apical processes, ovoid perikarya and a basal process. The ventral region of the 3rd ventricle becomes funnel-shaped on the 20th day of the prenatal period. As the cells differentiate, the apical process becomes shorter and broader. Moreover, on day 20 of prenatal life cells without apical processes appear. Their number increases during the postnatal period. The concentration of endoplasmic reticulum, mitochondria, polysomes, lipid droplets, dense bodies (lysosomes), lamellated and multivesicular bodies increases. Initially the cells are similar but from the 3rd day of postnatal life differentiation occurs in different regions of the infundibular recess. After the 5th day, there are no marked changes in the structure and distribution of these cells.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 157
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 201 (1979), S. 315-325 
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Post-natal development ; Neurohypophysial peptides ; Magnocellular and parvocellular neurons
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Immunocytochemical localization of vasopressin (VP), oxytocin (OXY) and neurophysins I and II (NI and NII) in the hypothalamus of growing rats revealed several new features. Hormones and neurophysins were present in magnocellular neurons of newborn rats: VP and NII in a first neuronal population, OXY and NI in a second neuronal population. For the first three days after birth, the ratio of detected VP to detected NII increased whereas the ratio of detected OXY to detected NI appeared constant. It was obvious that maturation of the OXY/NI magnocellular system occurred later than maturation of the VP/NII magnocellular system. During the first three weeks of development, VP/NII fibres in the median eminence were separated into two distinct groups: the hypothalamo-neurohypophysial tract in the internal part of the median eminence, and pericapillary endings heavily loaded with VP and NII in the external part of median eminence. OXY/NI fibres did not show this particular distribution. Therefore, during this post-natal period, loading of infundibular VP endings was related to the increase of ACTH synthesis demonstrated by various authors. Therefore, we suppose that simultaneous participation of VP and corticotropin-releasing hormone does not only appear during experimental and chronic stimulation of ACTH synthesis (after adrenalectomy, for example) but that it also exists during physiological stimulation of corticotropic function. At birth, parvocellular suprachiasmatic neurons were devoid of VP and NIL A slight immunological reactivity appeared in 6-to 10-day-old rats and it became equivalent to the immunological staining in the adult rat during the third post-natal week. Thus, the appearance of suprachiasmatic VP preceded the differentiation of the rhythmic activity of the pituitary adrenal axis. These chronological relationships suggest the involvement of the suprachiasmatic VP-related-peptide in the circadian periodicity of the corticotropic function.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 158
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 201 (1979), S. 377-408 
    ISSN: 1432-0878
    Schlagwort(e): Median eminence ; Tanycytes ; Nerve tracts ; Regional organization ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The structural organization of the rostral, lateral and postinfundibular regions of the median eminence (ME) of 5-day cyclic diestrous rats was studied with light and electron microscopic methods. The ependymal cells lining (i) the floor of the infundibular recess (IR) at rostral levels, (ii) the lateral extensions of the IR, and (iii) the floor of the premammillary recess appear to represent the same type of tanycyte ependyma (β1 tanycytes). In the entire width of the rostral and postinfundibular palisade regions, as well as in the lateral palisade region of the preinfundibular ME, the processes of the β1 tanycytes form a continuous cuff. This cuff separates the nerve endings from the blood vessels and the pars tuberalis. At this level, synaptoid contacts between neurosecretory axons and the ependymal cuff can be observed. The ultrastructural characteristics of the β1 tanycytes are described and their ependymal endings tentatively classified into three types. In the lateral regions of the ME, the Golgi study revealed the presence of two fiber systems: (i) one possessing a latero-medial trajectory and distributed in the subependymal region; (ii) the other formed by a loose longitudinal tract originating from neurons of the arcuate nucleus. Some functional implications of the cellular organization of the rat ME are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 159
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 201 (1979), S. 349-359 
    ISSN: 1432-0878
    Schlagwort(e): Hypothalamus ; Rat ; Somatostatin-containing neurons ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The rat hypothalamus was studied at the light microscopic level with the use of single and double immunocytochemical staining methods. It was shown that the rat supraoptic and paraventricular hypothalamic nuclei, and their accessory neurosecretory nuclei, do not contain magnocellular somatostatin neurons. The distribution of the hypothalamic parvocellular somatostatin cells is described. The parvocellular component of the rat hypothalamic paraventricular nucleus is, at least partly, composed of somatostatin cells: they form a fairly well circumscribed periventricular cell mass. The rat suprachiasmatic nuclei contain separate somatostatin neurons and vasopressin neurons. Scattered somatostatin cells are present in the entire arcuate nucleus. In addition to the periventricular somatostatin cells located in the preopticanterior hypothalamic area and in the arcuate nucleus, the rat hypothalamus also contains numerous scattered somatostatin cells located distant from the third ventricle.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 160
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Vasopressin ; Oxytocin ; Somatostatin ; Luteining hormone releasing hormone
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The hypothalamic hormones arginine-vasopressin (AVP), oxytocin (OXT), somatostatin (SOM), and luteinizing hormone-releasing hormone (LHRH) were localized in the rat neurohypophysis by the use of semithin serial sections and the unlabeled antibody enzyme method. Clusters of AVP fibres are present within the central region of the neural lobe, clusters of OXT fibres mainly in the peripheral part. The AVP fibres enter bilaterally into the neural lobe. The results call into question previous reports on the presence of AVP on receptors in the pars intermedia cells, since incubation with anti-AVP resulted in similar staining in the pars intermedia of the Wistar and homozygous Brattleboro rat, a mutant strain deficient in AVP. The same intermediate lobe cells are stained after incubation of serial sections with anti-AVP and anti-α-melanocyte-stimulating hormone (α-MSH). This staining of anti-AVP could be removed by solid phase absorption to α-MSH and is thus most probably due to cross reaction with α-MSH. SOM fibres appear to be present in the peripheral parts of the proximal neurohypophysial stalk and mainly lateral in its more distal parts. In the neural lobe they rapidly decrease in number, although some fibres continue into the distal part of the neural lobe, running bilaterally and situated adjacent to the pars intermedia. The SOM staining within magnocellular elements, which has been reported in the literature, can most probably be explained by cross reaction of anti-SOM with neurophysins. LHRH fibres are very scarce in the neurohypophysial stalk and absent in the neural lobe.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 161
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; ACTH ; Lymnaea stagnalis ; Neurohormone ; Neurotransmitter
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Two giant neurons (diameter 130 μm) were identified immunocytochemically by means of the unlabeled antibody enzyme technique with anti ACTH 1–39 and 1–24 in the pond snail Lymnaea stagnalis. The cells are located in the visceral and the right parietal ganglion, respectively. They contain moderately electron dense elementary granules (diameter 150–160 nm). By means of the intracellular horseradish peroxidase injection technique it was shown that the cells send fibres into the neuropiles of various ganglia and into nerves. Synapses occur on the fine fibre branches in the neuropile. Synapse-like structures were found on the cell bodies and on the major fibres. The giant neurons are electrotonically coupled. With toluidine blue staining for small peptides it was demonstrated that in the central nervous system of the pond snail numerous peptidergic neurons occur in addition to those identified with the classical staining methods for neurosecretion.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 162
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 188 (1978), S. 345-359 
    ISSN: 1432-0878
    Schlagwort(e): Hippocampal subfields ; Rat ; Volumes ; Timm stain
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The absolute volumes of the hippocampal and subicular cortical layers in the rat were determined. The boundaries of the various layers were defined on series of sections made through the entire hippocampal region of five rats and stained according to the Timm sulfide silver technique. Coordinates representing the boundaries of the layers on selected sections were fed into a mini-computer programmed to calculate the volume of the layers from the areas of the profiles and the distances between the sections. The distribution of the layers indicates that they constitute the same proportion of the volume of the dorsal and ventral divisions of the hippocampal region, with the exception of the structures lying in regio inferior and regio superior. Although the combined regio superior and regio inferior components of the layers of Ammon's horn occupy the same percentage of the volume of the dorsal and ventral hippocampal regions, the regio superior components occupy a larger percentage of Ammon's horn in the dorsal region than they do in the ventral region. The inter-animal variations in the volumes of the various layers indicate that it is possible to describe quantitatively the subdivisions of the hippocampal region with a precision that is compatible with comparative studies.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 163
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 188 (1978), S. 491-496 
    ISSN: 1432-0878
    Schlagwort(e): Castration ; LH-cells ; Rat ; Development ; Sex-steroids
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The effects of sex-steroids on the LH-cell development in neonatal rats were studied. The cells were stained immunohistochemically by applying anti-HCG serum. On the second day after birth some of the animals of both sexes were gonadectomized and simultaneously injected with testosterone or estradiol (50 or 200 μg). The remaining animals were either gonadectomized or injected with either one of the sex-steroids. The LH-cell numbers in each group were determined on the 12th day of age from serially cut histological sections of the pituitary. In castrated males the number of LH-cells was about twice that of the intact animals. In the so-called sex-zone, LH-cells tended to be hypertrophied in castrates. These alterations in the appearance of LH-cells did not occur after ovariectomy. In gonadectomized animals injected with sexsteroids (200 μg), the cells were markedly reduced in number and size, both in males and females. Testosterone injection (50 μg) into intact newborn animals also suppressed the numerical development of LH-cells, especially in females. These alterations were particularly evident in the sex-zone in both sexes. Thus the present findings show that sex-steroids may be involved in sexual differences in morphological development of LH-cells in newborn rats.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 164
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 209 (1980), S. 1-10 
    ISSN: 1432-0878
    Schlagwort(e): Myoepithelial cell ; Exocrine gland ; Scanning electron microscopy ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary By removing connective tissue components with enzymatic digestion followed by HCl-hydrolysis, myoepithelial cells (MECs) of the terminal portion in a variety of exocrine glands of the rat were examined with the scanning electron microscope. The profile of MECs varied considerably from gland to gland; MECs in the lactating mammary gland have a few long cytoplasmic processes in close contact with those of adjacent cells forming a continuous network around the terminal portion. Those of the exorbital lacrimal gland are stellate with many thin radiating processes with tapered ends that terminate freely. MECs in the sublingual gland are characterized by a number of broad and extensive cellular processes. MECs in the submandibular gland are similar in appearance to those of the exorbital lacrimal gland, but with more extensive cellular processes that form a more or less continuous network with those of the adjacent cells. No MECs were observed on the terminal portion of the parotid gland where the cells appear to be lodged on the intercalated duct. The relative surface area covered by MECs per terminal portion was also found to vary significantly, being 24% in the lactating mammary, 17% in the exorbital lacrimal, 48% in the sublingual, and 25% in the submandibular glands. The findings are discussed in relation to the physical properties of secretions in different glands.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 165
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 189 (1978), S. 403-407 
    ISSN: 1432-0878
    Schlagwort(e): Adrenal gland ; Rat ; Vinblastine ; Corticosterone ; Exocytosis
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Vinblastine treatment blocks corticosterone release from rat adrenal zona fasciculata without impairing hormone synthesis, and induces the formation of acid phosphatase-positive granular clumps at the juxta-sinusoidal pole of the cells. Autoradiography shows that ACTH administration to vinblastine-treated animals mobilizes the 3H-cholesterol stored in the lipid droplets and leads to a noticeable labelling of the granular clumps. The possible significance of these granules is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 166
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 206 (1980), S. 355-365 
    ISSN: 1432-0878
    Schlagwort(e): LRH neurons ; Prosimians (Tupaia, Galago) ; Fluorescence ; microscopy ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Reactive LRH neurons were characterized in prosimians (Tupaia and Galago) by immunofluorescence using rabbit immunesera against unconjugated synthetic LRH, or LRH conjugated with bovine serum albumin. These neurons, which vary individually in number in one species, are mainly concentrated in the rostral hypothalamus (medial preoptic area and anterior hypothalamic area) and in the lamina terminalis. In contrast to the simians and man, immunoreactive perikarya were not routinely found in the mediobasal hypothalamus of the prosimians investigated in the present study. Reactive axons of the hypothalamo-hypophyseal tract are more numerous and conspicuous in the retrochiasmatic area and in the postinfundibular eminence. They give rise to radiating collaterals ending mainly around the capillaries of the primary portal plexus of the median eminence and of the infundibular stem (where they are generally more numerous). Reactive axons of the preopticoterminal tract, originating from the perikarya of the lamina terminalis, end around the capillaries of the vascular organ or below and between the ependymal cells lining its ventricular side. In Galago a small but very distinct tract of reactive axons runs under the optic chiasma, between the lamina terminalis and the ventral labium of the infundibulum. Very fine reactive extrahypothalamic axons were observed in the posterior part of the habenular ganglia, along the preamygdaloid portion of the stria terminalis and along the blood vessels of the parolfactory area.
    Materialart: Digitale Medien
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  • 167
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 207 (1980), S. 89-107 
    ISSN: 1432-0878
    Schlagwort(e): Rehydration ; Nongranular vasopressin ; Intercellular clefts ; Axoplasmic reticulum ; Ultrastructural immunocytochemistry ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The vasopressin system of the rat was examined in the course of the first 12 h of rehydration after prolonged thirst at light and electron microscopic levels and by use of the peroxidase anti-peroxidase (PAP) method. Light microscopically, the median eminence was the only part of the system that not only displayed distinct differences between animals of different rehydration times but also showed a characteristic pattern of immunohistochemical reactivity in its rostro-caudal distribution. Ultrastructurally, in the perikarya a maximal labeling of the rough endoplasmic reticulum was observed after 2 h of rehydration, whereas an extensive labeling of the enlarged Golgi zones was attained after 4 h of resupplying water. A labeling of the intercellular clefts in the basal glial labyrinth of the supraoptic nucleus (and to a lesser degree in the subependymal neuropil adjacent to the paraventricular nucleus) was increased 30 min after the onset of drinking, as compared with water-deprived animals; it decreased slightly after 12 h of rehydration. The filling of the swollen fibers by increasing amounts of labeled axoplasmic reticulum, evident in the nuclear areas already after 30 min of water supply, begins in the median eminence after 2 h of rehydration and is fully developed after 4 and 8 h. Corresponding results hold true for the neural lobe but are somewhat delayed in comparison to the findings in the median eminence. The discussion considers (i) synthesis and transport of nongranular vasopressin within the axoplasmic reticulum, and (ii) release not only from the neural lobe but also from the nuclear areas and from the fibers of the median eminence.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 168
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 211 (1980), S. 331-343 
    ISSN: 1432-0878
    Schlagwort(e): Gut hormones ; Endocrine cells ; Electron microscopy ; Immunocytochemistry ; Peptidergic innervation
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Histological, cytochemical and immunocytochemical methods were used in light and electron microscopical studies to demonstrate the presence of a neuroendocrine system in the gut of the urodele, Salamandra salamandra. Cytochemical stains capable of detecting peptide-producing endocrine cells demonstrate cells reacting with Masson's silver (argentaffin) method, Grimelius' argyrophil silver method, masked metachromasia method and the lead haematoxylin stain. Using antisera raised to a variety of mammalian gut peptides, cells containing bombesin-, gastrin-, somatostatin-, substance P- and glucagon-like immunoreactivity were identified; vasoactive intestinal polypeptide- and substance P-like immunoreactivities were found in nerve fibres in the submucous and myenteric plexus. No immunoreactivity was detected for motilin, gastric inhibitory polypeptide, cholecystokinin or secretin. The ultrastructure of the immunoreactive cells and nerves was revealed by the semithin/thin method. All the cells identified contained numerous electrondense secretory granules, which varied in their chracteristic morphological structure from one cell type to another. The evidence collected in this study indicates that a complex neuroendocrine system regulating gut function is present in this amphibian and may have developed prior to the emergence of the phylum.
    Materialart: Digitale Medien
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  • 169
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Biologically active peptides ; Lymnaea stagnalis ; Neurohormone ; Neurotransmitter
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Perikarya and nerve fibers were immunocytochemically identified in the central nervous system of the pond snail Lymnaea stagnalis by means of the unlabelled antibody enzyme method with antisera to 15 biologically active peptides of vertebrates: vasopressin, vasotocin, oxytocin, α-melanocyte stimulating hormone (α-MSH), met-enkephalin, somatostatin, glucagon, insulin, glucose-dependent insulinotropic peptide (GIP), vaso-active intestinal polypeptide (VIP), gastrin, secretin, pancreatic polypeptide (PP), Substance P, calcitonin. No immunostaining was obtained with antisera to β-endorphin, cholecystokinin (CCK), neurophysin I and II. Particular neurons could be identified with two antisera (anti-vasopressin/vasotocin, anti-α-MSH/metenkephalin, anti-substance P/PP, anti-PP/gastrin). Apparently this indicates that populations of cells identified with a given antiserum may consist of more than one cell type. Only a few of the new peptidergic cells appeared to be identical with classical neurosecretory cells. Thus the growth hormone producing Light Green Cells stained with anti-somatostatin and the axon terminals of the ovulation hormone producing Caudo-Dorsal Cells with anti-met-enkephalin. Whether this indicates structural identity of the growth hormone with somatostatin and of the ovulation hormone with met-enkephalin remains to be investigated. Just like the classical neurosecretory cells a number of the new peptidergic cells (anti-glucagon, -insulin, -met-enkephalin, -somatostatin, and -PP positive cells) send their axons to the peripheries of commissures, connectives or nerves. Thus these cells can be considered as probably neuroendocrine. The classical neurosecretory cells release their products into the haemolymph from these sites. Other new peptidergic cells (e.g., anti-vasopressin, -vasotocin, -oxytocin and -GIP positive cells) have axons that terminate, probably synaptically, on other neurons, indicating that they are “more conventional” neurons, their products being neurotransmitters/neuromodulators. It can also not be excluded that some cells of a population containing a given peptide are neuroendocrine and others make contact with other neurons.
    Materialart: Digitale Medien
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  • 170
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 233 (1983), S. 69-80 
    ISSN: 1432-0878
    Schlagwort(e): Somatostatin ; Hypothalamus ; Immunocytochemistry ; Human ; Rhesus monkey
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Immunocytochemical methods were used to compare the localization of somatostatin (SRIF) in the human and rhesus monkey hypothalamus. The distribution of SRIF-containing cell bodies and fibers is similar in the two species. Perikarya are located predominantly in the periventricular region and to a lesser extent in the ventromedial nucleus. Fibers occur in dense clusters within the periventricular region, ventromedial nucleus, arcuate nucleus, median eminence, and pericommissural area of both species. Analysis of serial sections suggests that fibers originate from cells in the periventricular region, extend ventrally through the ventromedial and arcuate nuclei to terminate around the portal vessels of the infundibular stalk, and thereby participate in the regulation of anterior pituitary function. Somatostatinergic fibers are also found surrounding non-immunoreactive perikarya in the ventromedial nucleus and periventricular region of both primates. This arrangement may support somatostatin's postulated role as a neurotransmitter or neuromodulator. The strong similarity between the localization of hypothalamic SRIF in the human and rhesus monkey supports the use of the rhesus monkey as a model for the study of somatostatin as a neuroendocrine regulator in the human.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 171
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 233 (1983), S. 23-33 
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Vasopressin ; Dorsomedial hypothalamus ; Amygdala ; Locus coeruleus
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Recently, the existence of a vasopressin-immunoreactive cell group was described in the bed nucleus of the stria terminalis (van Leeuwen and Caffé 1983). In the present investigation additional nuclei containing vasopressin-immunoreactive cells were found, after colchicine pretreatment, in the dorsomedial hypothalamus, medial amygdaloid nucleus and the locus coeruleus. Vasopressin-immunoreactive cells in the dorsomedial hypothalamus and medial amygdaloid nucleus are small (8–14 μm and 10–14 μm, respectively), while those in the locus coeruleus are medium-sized (20–25 μm). Incubation with anti-bovine neurophysin II and anti-rat neurophysin revealed staining of the same cell group in the above-mentioned areas. None of these cell groups show stained cells after incubation with anti-oxytocin and anti-bovine neurophysin I. When sections of the homozygous Brattleboro rat, which shows a deficiency in vasopressin synthesis, are incubated with anti-vasopressin, anti-bovine neurophysin II, or anti-rat neurophysin, no immunoreactivity can be observed in these brain regions. The above-mentioned cell groups may contribute to the vasopressinergic innervation of brain sites that have been reported to persist after lesioning of the suprachiasmatic, paraventricular and bed nuclei of the stria terminalis.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 172
    ISSN: 1432-0878
    Schlagwort(e): α-Endorphin ; Immunocytochemistry ; Median neurosecretory cells ; Peptidergic neurones ; Calliphora vomitoria
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary A group of the 24–26 paraldehyde fuchsin-positive median neurosecretory cells (MNC) in the pars intercerebralis of the brain of the blowfly, Calliphora vomitoria, has shown immunoreactivity towards three different antibodies to α-endorphin, a peptide that corresponds to the amino acid sequence present between residues 61 and 76 of the precursor molecule, β-lipotropin (β-LPH). The immunoreactive material could be followed in axons within the median bundle, the tract through which neurosecretory material from the MNC is passed down to the corpus cardiacum (CC). The α-endorphin-immunoreactive material was observed leaving the CC in the cardiac-recurrent nerve, dorsal to the proventriculus, in the direction of the abdomen. The cells that contain the α-endorphin-like material are different from those of the MNC that contain insulin-, pancreatic polypeptide-, and gastrin/CCK-like peptides. This finding demonstrates the considerable complexity and peptidergic nature of the MNC and constitutes further evidence that morphinomimetic-like peptides are present in the nervous system of invertebrates.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 173
    ISSN: 1432-0878
    Schlagwort(e): Angiotensinogen ; Liver ; Kidney ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The renin substrate, angiotensinogen, was localized by immunocytochemistry in liver and kidney of normal rats by the use of an antiserum directed against pure rat angiotensinogen. This substrate was also examined in rats after bilateral nephrectomy, which is known to increase plasma angiotensinogen, and in rats treated with colchicine, which inhibits serum protein secretion. In normal rat liver, light microscopy showed the presence of immunoreactive material in a very few cells. The number of stained hepatocytes rose in rats treated with colchicine or after bilateral nephrectomy. Immuno-staining increased further when rats were both nephrectomized and colchicine treated. In the kidney, angiotensinogen was specifically located as granular formations in nephrocytes of the proximal tubule but never in the granular cells of the juxtaglomerular apparatus. The localization of these granular formations under the brush border suggests that angiotensinogen is reabsorbed from the glomerular ultrafiltrate rather than synthesized in the kidney.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 174
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 233 (1983), S. 471-474 
    ISSN: 1432-0878
    Schlagwort(e): Prolactinergic neurons ; Immunocytochemistry ; Cerebral ganglion ; Styela plicata
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Peptidergic neurons have been detected in the cerebral ganglion of the ascidian Styela plicata by means of cytochemical methods. After incubation with a mammalian antibody to human prolactin the perikarya show a strong immunoreactivity. The possible function of prolactin-like peptides in the nervous system of protochordates is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 175
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 233 (1983), S. 485-505 
    ISSN: 1432-0878
    Schlagwort(e): Liver ; Pit cell ; Cytoplasmic granules ; Vesicles ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Pit cells, on which almost no further contributions have been presented since the first report by Wisse et al. (1976), are described in detail in the rat liver. These cells show several characteristic features: 1) “rod-cored vesicles”, a new type of vesicular inclusion observed first in our study; 2) electron-dense granules, which we consider to arise from multivesicular bodies by the accumulation of dense material; and 3) well-developed pseudopodia. Although these features clearly differentiate pit cells from conventional lymphocytes, these two cell types display similarities (i) in a number of ultrastructural features, (ii) in the pattern of their intralobular distribution, and (iii) in their presence in the spleen and peripheral blood.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 176
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 233 (1983), S. 689-691 
    ISSN: 1432-0878
    Schlagwort(e): Fluoride ; Progeny ; Bone ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Femurs of weanling rats from third-pregnancy litters of dams given 150 ppm fluoride in the drinking water were examined by light- and scanning-electron microscopy. Under the conditions of the experimental procedure, no pathological changes were seen in the femurs as a result of maternal ingestion of fluoride. These results indicate that the amount of fluoride crossing the placenta and mammary gland was insufficient to produce significant morphological changes in the bones of 3-week-old rats.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 177
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 234 (1983), S. 125-134 
    ISSN: 1432-0878
    Schlagwort(e): Vasopressin ; Immunocytochemistry ; Electron microscopy ; Hypothalamus ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Vasopressin-containing neurons, identified by immunocytochemistry, are located predominantly in the posterior magnocellular division of the paraventricular nucleus of the rat hypothalamus. By electron microscopy, the immunoreaction product is seen within the cell bodies and neuronal processes. In the perikarya and dendritic processes, the immunoreactive material is associated primarily with neurosecretory granules. Axonal processes, identified by their content of microtubules and accumulation of neurosecretory granules, show the immunoreaction product in association with both of these organelles. Afferent axo-dendritic, axo-somatic and putative axo-axonic synapses with immunostained vasopressinergic neurons can be identified. The presynaptic profiles do not contain immunoreactive material. This study contributes to the ultrastructural characterization of vasopressinergic neurons in the paraventricular nucleus and of their afferent synaptic input.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 178
    ISSN: 1432-0878
    Schlagwort(e): Fibronectin ; Lung ; Development ; Ultrastructure ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In a previous study changes in the macrodistribution of fibronectin during rat-lung development were examined. Using the peroxidase-antiperoxidase immunocytochemical technique, we have demonstrated the presence of fibronectin in embryonic, neonatal, and adult rat lung at the ultrastructural level. In the embryo, fibronectin is found both in an intra-and extracellular association with isolated pneumoblasts, and in a periodic distribution along the basal lamina. The neonate displays fibronectin in an intracellular association with early type-I cells and on their basal and luminal surfaces, but not in association with type-II cells. Neonatal basal lamina is diffusely labeled by anti-fibronectin antiserum. Fibronectin in adult tissue is found both intracellularly and on the basal and luminal surfaces of type-I cells but not in type-II cells. The basal lamina and interstitial connective tissue are slightly or non-reactive. These observations confirm and extend our initial suggestion that fibronectin is involved in rat-lung development.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 179
    ISSN: 1432-0878
    Schlagwort(e): Hypothalamo-hypophysial system ; Capillaries ; Ontogenesis ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The maturation of the capillaries of the primary portal plexus in rats during the perinatal period has been studied lightand electronmicroscopically. The number of capillaries covering the median eminence and of those invading the nervous tissue (capillary loops) increases significantly with age. Capillary loops were observed as early as the 18th fetal day. The mitotic divisions of the endothelial cells within the preexisting capillaries seem to be the main reason for the vascular growth. Immature capillaries with a characteristic narrow lumen are surrounded by a fuzzy basal lamina; their wall is formed by a generally expanded endothelium with rather sparse organelles and inclusions, and by minute flattened areas. The maturation of the capillary results in a progressive spread of flattened endothelium followed by an enlargment of the capillary lumen. Moreover, a rising concentration of organelles and inclusions, relatively numerous luminal microvilli, and a dense and uniform basal lamina become noticeable as capillary differentiation proceeds. These data are thought to reflect the progressive increase in the metabolic activity of the endothelium as well as the establishment of capillary patency during the perinatal period of rats.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 180
    ISSN: 1432-0878
    Schlagwort(e): Urotensin ; Caudal neurosecretory system ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The localization of urotensin I has been investigated in the caudal neurosecretory system of the white sucker (Catostomus commersoni). The peptide is present in all the cells of the system both large and small, in the large axons passing to the urophysis, and in fine beaded fibres not only within the urophysis but also in a fine plexus lateral to the large cells in the spinal cord proper. The possibility that the caudal neurosecretory system is not a functionally uniform system but rather a collection of dissimilar cells of different synaptic inputs with a common entity, urotensin I, is discussed. Moreover, the feasibility of a urotensin I feedback loop is described.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 181
    ISSN: 1432-0878
    Schlagwort(e): Pituitary rat ; LH cells ; FSH cells ; ACTH cells ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary By means of immunocytochemistry, the development of ACTH-, LH- and FSH cells was examined in the anterior pituitary of 5-day-old neonatal, 15-day-old immature and adult rats. ACTH-positive cells are angular and the periphery of these cells is strongly reactive with anti-ACTH serum. In contrast, LH- and FSH-immunopositive cells are ovoid elements, ranging in cell size and intensity of staining. Angular cells, in which only the cell periphery reacted with anti-LHβ serum, were observed in neonatal and immature rats; however, these cells were not stained with either anti-FSHβ serum or anti-ACTH serum. Observation of serial semithin sections revealed that ACTH-immunopositive cells do not react with either anti-LHβ or anti-FSHβ serum. Finally, it was observed that ACTH cells and LH cells are both functionally differentiated already in 5-day-old neonatal rats.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 182
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 77-83 
    ISSN: 1432-0878
    Schlagwort(e): Pituitary (rat) ; LH cells ; FSH cells ; Rapid freeze-substitution ; Immunocytochemistry ; Ferritin antibody
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Rapid freeze-substitution fixation was employed in immunocytochemical studies on the localization of LH and FSH in the typical gonadotrophs of the anterior pituitary in the untreated male rat; a modification of a recently described ferritin antibody method (Inoue et al. 1982) was used in these studies. It was shown that rapid freeze-substitution fixation provides good preservation not only of the ultrastructure but also of the antigenicity. Both LH and FSH were clearly demonstrated in the same gonadotrophic cells, but the subcellular localization of these gonadotrophins differed: (i) LH was mainly located in small secretory granules, 250–300 nm in diameter; (ii) FSH was mainly present in large secretory granules, up to 500 nm in diameter. In the pituitary gland of the adult male rat, all gonadotrophs that react to antibodies against gonadotrophins are characterized by small and large secretory granules. Other types of cells of the anterior pituitary containing either small secretory granules or resembling corticotrophs with secretory granules assembled at cell periphery did not react to either anti-LH beta or anti-FSH beta serum. For light microscopy, the peroxidase antibody method was used. All of the gonadotrophin-positive cells contain both LH and FSH. None of the pituitary cells reacted to antibody against only one gonadotrophin. However, some cells are “LH-rich” while other cells are “FSH-rich”.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 183
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 159-169 
    ISSN: 1432-0878
    Schlagwort(e): Anterior pituitary ; Gonadotropic cells ; Immunocytochemistry ; Testosterone binding ; Cryo-ultramicrotomy
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Several attempts have been made to localize steroids by means of immunocytological techniques. However, these methods were found inadequate for detecting steroids bound to their receptors. To localize endogenous testosterone (T) in its target cells at the ultrastructural level, an immunocytological technique was performed on ultrathin sections obtained by cryo-ultramicrotomy. T was detected in the pituitary glands obtained from intact male or female rats and castrated rats, but not in castrated + adrenalectomized rats. Animals were also injected either with testosterone, with other steroids (estradiol, progesterone, corticosterone) or with an androgen antagonist (cyproterone acetate). In addition, some ultrathin sections were preincubated either with phosphate buffers of various pH, corticosterone, cyproterone acetate solution, or with T solution. The content of T in the pituitary before and after fixation was measured by radioimmunoassay; it decreased after fixation. T immunoreactivity was localized in the gonadotropic cells only, both in the male and female rats. At the subcellular level, the immunoreactivity was detected in the cytoplasmic matrix and in the nucleus. Immunoreactive T disappeared 1) in rats after castration+adrenalectomy; by means of radioimmunoassay no T was measured in these pituitary glands; 2) in rats injected with 25 (μg/rat of cyproterone acetate; 3) after preincubation of pituitary sections on a drop of cyproterone acetate (1 × 10-6 M). The immunocytological reaction was not modified when the rats were injected with estradiol, progesterone or corticosterone (1 mg/rat), or after preincubation of the sections with corticosterone (1 × 10-3 M), or a buffer solution at pH 7.6. Lower or higher pH values led to a strong decrease in the immunoreactivity. After injection of T (15 μg/rat) the immunocytological reaction was more abundant in the nucleus and less in the cytoplasm. The immunoreactivity was again observed when the sections were preincubated with cyproterone acetate solution and then with T solution. These data suggest that T can be detected by means of immunocytochemistry. It is probably bound to a specific binding site.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 184
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 187-194 
    ISSN: 1432-0878
    Schlagwort(e): Golgi apparatus ; Monensin ; Small intestine ; Cytochemistry ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The effect of short-time treatment with the ionophore monensin, administered intraluminally at concentrations of 5 and 10 μM, was studied on the Golgi apparatus of absorptive cells in the small intestine of the rat. At 2–3 min after treatment most of the Golgi stacks exhibited dilated cisternae. At 4–5 min stacked cisternae were absent; they were replaced by groups of smooth-surfaced vacuoles. Dilatation and vacuolization occurred in the entire stacks without preferential effect on any particular Golgi subcompartment. Monensin did not influence the cytochemical Golgi reaction of thiamine pyrophosphatase and acid phosphatase. The characteristic staining pattern of these two enzymes in all Golgi cisternae of absorptive cells in the proximal small intestine, and the reactivity restricted to trans cisternae in distal segments of the small intestine, were unchanged after treatment with monensin. In the distal small intestine, the cytochemical pattern allowed the monensin-induced vacuoles to be attributed to the former cisor trans-Golgi face. Further, the cytochemical results demonstrate that vacuolization is not restricted to the stacked cisternae, but includes the trans-most cisterna. The latter, usually located at some distance from the Golgi stacks, has been defined as belonging to the GERL system in several types of cells. The clear response to monensin, an agent that selectively affects the Golgi apparatus, indicates common properties between trans-most and stacked Golgi cisternae.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 185
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Supraoptic nucleus (SON) ; Oxytocin neurones ; Neuronal appositions
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Pre-embedding immunocytochemistry was performed on vibratome sections of the hypothalamus of lactating rats using antiserum directed against oxytocin. Electron microscopy revealed that numerous immunopositive somata and dendrites in the supraoptic nucleus were in direct apposition, without glial interposition; a number of them were also bridged by “double” synapses. The observations support the contention that the ultrastructural reorganisation of the nucleus apparent at lactation affects the magnocellular neurones secreting oxytocin.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 186
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 427-432 
    ISSN: 1432-0878
    Schlagwort(e): DPP IV ; Salivary glands ; Ultrastructural localization ; Immunocytochemistry ; PAP
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The ultrastructural localization of dipeptidyl peptidase IV (DPP IV) (EC 3.4.14.5) in rat submandibular and parotid glands was studied immunocytochemically by the peroxidase-antiperoxidase (PAP) method, using a monospecific antiserum against rat kidney DPP IV. There were no differences in the immunocytochemical localization of DPP IV between submandibular and parotid glands. In these glands, DPP IV was primarily found to be associated with the luminal and intercellular canalicular plasma membranes of acinar cells and with the luminal plasma membranes of intercalated and striated duct cells. Occasionally, immunoreaction of DPP IV was detected in cytoplasmic vesicles (vacuoles), lysosomes, and multivesicular bodies in some acinar cells as well as in ductal epithelial cells. Furthermore, the reaction product was also found within the lumina of peri-acinar and peri-ductal capillaries and in the cytoplasm of some fibroblasts in the interstitial connective tissue. These data suggest that DPP IV in the submandibular and parotid glands may play some role in the secretion or reabsorption processes of secretory proteins and peptides in these glands.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 187
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 485-489 
    ISSN: 1432-0878
    Schlagwort(e): Ventromedial nucleus ; Hypothalamus ; Ultra-structure ; Nucleoli ; Estrogen effects ; Chromatin ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Estrogen is accumulated from the blood by nerve cells in the ventromedial nucleus of the hypothalamus and can facilitate female reproductive behavior by acting on this region of the brain. This cell group was examined in ovariectomized female rats, given estrogen or control treatment, by use of light and electron microscopy. A significantly greater portion of the nerve cells in the estrogen-treated animals had protuberances on their nucleolar surfaces, apparent under the light microscope. The fine structure of such protuberances included dense, aggregated material, which is shown to contain DNA by the sodium tungstate staining technique. Because increased numbers of such protuberances were found in nuclei of cells of the experimental group where previous studies demonstrated a significant increase in ultrastructural signs of biosynthetic activity, they may be associated with increased RNA synthesis. Thus, they could indicate, ultrastructurally, increased synthetic rates for RNA in nerve cells through which estrogen promotes reproductive behavior.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 188
    ISSN: 1432-0878
    Schlagwort(e): S-100 protein ; Thymus ; Interdigitating cells ; Immunocytochemistry ; Man
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The present study deals with the localization and ultrastructure of S-100-immunoreactive cells in the human thymus. These immunoreactive cells are distributed mainly in the medulla with some scattered elements in the cortex. Electron-microscopic observation revealed that the cells are characterized by an irregularly shaped nucleus, tubulovesicular structures in the cytoplasm and characteristic interdigitations of the plasma membrane. The cells often embrace lymphocytes with their branched processes. On the basis of these morphological features, the immunostained elements were identified as interdigitating cells (IDCs). The immunocytochemistry for S-100 visualizes the precise distribution and extension of the IDCs under the light microscope and indicates that the IDCs form no structural networks such as those established by the thymic epithelial cells. Since the IDCs in human lymph nodes have also been reported to contain S-100-like immunoreactivity, S-100 protein can be regarded as a useful marker for identifying the IDCs in the human thymus and other lymphoid organs.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 189
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; FMRF-amide ; Neurotransmitter ; Palaemon
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary By use of a specific antiserum against the molluscan cardio-excitatory tetrapeptide FMRF-amide in combination with the PAP-method it was possible to obtain positive immunocytochemical reactions in several neurosecretory regions of the eyestalk of the prawn Palaemon serratus. FMRF-amide-like material was found in perikarya and nerve fibers of the medulla terminalis and in neurons in the lamina ganglionaris. The immunoreactivity observed in the glandular tissue located at the basal insertion of the eyestalk muscles must be ascribed to a non-specific reaction. The identification of immunopositive nerve fibers, ending on a nerve bundle in the medulla terminalis, and the fact that immunoreactive material was absent in the neurohemal sinus gland seem to indicate a neurotransmitter/neuromodulator function.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 190
    ISSN: 1432-0878
    Schlagwort(e): Fetal porcine pituitary ; ACTH, MSH, β-LPH, α- and β-endorphin, GH, PRL ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The aim of the present study on the fetal porcine pituitary was (1) to detect by means of the immunoperoxidase technique the earliest stages of cells producing polypeptide hormones: β-MSH, ACTH, β-LPH, α- and β-endorphin, growth hormone (GH) and prolactin (PRL), (2) to study the development of the synthesis and the storage of these hormones during fetal life, and (3) to detect whether several hormones can be located in one and the same cell. The corticotropic cells were revealed as the earliest functional elements of the fetal anterior pituitary. Our results indicate clearly that ACTH, β-MSH, β-LPH, α- and β-endorphin appear at 34 days in the same regular, round or ovoid cells; no differences in the time of their appearance could be observed. The ACTH-cells, irregular or angular in shape and endowed with cytoplasmic processes such as described in the adult pituitary, were not seen until day 50. The first GH-cells were detected between 40 to 45 days of fetal life. From day 45 to 90, the GH-cells greatly increased in number and in staining intensity of their progressively extending cytoplasmic area, but they displayed the same regular and round shape. The PRL-cells were the last cell type to appear in the fetal pituitary. The first PRL-cells, small in size and round or ovoid in shape with a high nucleus/cytoplasm ratio, were detected at day 70. At day 80, the PRL-cells increased in size and staining intensity. They displayed an irregular elongated or stellated shape and cytoplasmic processes resembling those characteristic of the adult pituitary. These data suggest that in the fetal porcine pituitary: (1) ACTH, β-LPH and related peptides are synthesized and stored in the same cells, and (2) PRL and GH appear in individual cellular elements.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 191
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 235 (1984), S. 669-673 
    ISSN: 1432-0878
    Schlagwort(e): Liver-cell heterogeneity ; Hepatic venous branches ; Karyometry ; Binucleate cells ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary In untreated adult male albino rats nuclear volume and the percentage of binucleate cells were determined in the first layer of hepatocytes adjacent to hepatic venous branches of varying diameters (〈40 μm, 40 μm–80 μm, 80 μm–120μm, 120 μm–160 μm, 〉160 μm), and in the third and fourth layer of hepatocytes in the remainder of the perivenous parenchyma. In the first layer of hepatocytes adjacent to the vascular structures means of nuclear volume are significantly lower and percentage of binucleate cells significantly higher than in the cells of the remainder of the perivenous parenchyma. Within each area measured distribution curves of nuclear volume classes were homogeneous but showed heterogeneity in comparison with each other. The morphometric data presented in this study strongly support the opinion of the heterogeneity of liver cells in the perivenous zone, as previously postulated on the basis of histochemical investigations.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 192
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 305-315 
    ISSN: 1432-0878
    Schlagwort(e): Hepatocytes ; Rat ; Liver ; Circadian rhythm ; Morphometry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Subcellular structures of hepatocytes in periportal and perivenous zones were examined during 24 h. The volume, surface and numerical profile densities of cytoplasmic organelles were analysed morphometrically. Most subcellular structures in periportal and perivenous hepatocytes were subject to strong circadian variations. In hepatocytes from both zones, the volume densities of smooth endoplasmic reticulum (sER), mitochondria, lysosomes, peroxisomes, polysomes and lipid droplets demonstrated peak values at 16.00 h, 20.00 h or 00.00 h; trough values were at 04.00 h, 08.00 h, or 12.00 h, except for peroxisomes (16.00 h). However, the volume densities of glycogen granules and rough endoplasmic reticulum (rER) in periportal and perivenous hepatocytes exhibited maximal values at 04.00 h, 08.00 h or 12.00 h and minimal values at 20.00 h. The surface densities of sER, mitochondria, lysosomes and peroxisomes, and the numerical profile densities of mitochondria, lysosomes and peroxisomes in periportal and perivenous hepatocytes showed similar trends. These events suggest that membranes of the rER show a partial correlation with the sER, mitochondrial and lysosomal membranes during the 24-h span. This may involve the interaction between ribosomes and rER. Almost all cytoplasmic organelles examined displayed significant differences between periportal and perivenous hepatocytes, morphometrically and in fine structure, indicating that the morphofunctional variability of hepatocytes differs depending on the location in the liver acinus.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 193
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 321-325 
    ISSN: 1432-0878
    Schlagwort(e): Triiodothyronine ; Radioautography ; Mitochondria ; Liver ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary To assess the distribution of the thyroid hormone triiodothyronine (T3) within intact living cells, freshly prepared dispersed rat hepatocytes were incubated with [125I]-T3 for periods of 5 min and 30 min. Lightand electron-microscopic (EM) radioautography was carried out to determine the distribution of grains over the isolated cells. Both procedures showed the grains distributed almost entirely over the cytoplasmic matrix rather than the nucleus. Grain counts under the EM were compared with expectation based on established quantitative methods. Only the mitochondria showed obvious and statistically significant grain counts, whereas the nucleus failed to accumulate grains in excess of expectations by chance alone based on area. The findings support the existence of mitochondrial binding of T3, presumably a prerequisite for its action in direct stimulation of the mitochondria.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 194
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 351-355 
    ISSN: 1432-0878
    Schlagwort(e): Lymph node ; Steroids ; Macrophages ; Intercellular junctions ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Intercellular junctions were often found between macrophages in sinuses of regional lymph nodes of the rat after injection of large doses of cholesterol, cortisone acetate, and estrone at the footpad. They were identified by subplasmalemmal densities, 20–50 nm in width, beneath the plasma membranes of apposed macrophages. No distinct filamentous structures were visible in those dense regions. Electron-dense amorphous materials are lined up at the center of the intercellular space in the junctional regions. Some macrophages form clusters with intercellular junctions. No significant difference in the effect of cholesterol, cortisone acetate, and estrone on the number of intercellular junctions betwene macrophages was found.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 195
    ISSN: 1432-0878
    Schlagwort(e): Anterior pituitary, porcine ; Gonadotropic hormones (FSH, LH) ; Immunocytochemistry ; Cellular compartments
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Pre- and post-embedding immunocytochemical methods based on the use of specific antibodies against β-subunits of porcine LH and FSH were applied to determine the changes occurring in the anterior pituitary of the pig after gonadectomy. The results showed that (1) the total number of immunoreactive gonadotropes increased from 21–25% in control animals to 24–37% in castrated animals; (2) all gonadotropes contained both LH and FSH; (3) several types of immunoreactive LH/FSH cells were revealed; and (4) the two immunocytochemical methods used with dispersed cells localized the hormones in the same subcellular sites. However, the staining intensity in the different locations varied depending on the method applied. With the post-embedding method, a dense reaction product was found in the secretory granules but the cisternae of RER and the Golgi saccules were always slightly reactive. After the pre-embedding method, the staining intensity in the RER-cisternae and in the Golgi saccules was greatly increased. Thus, the two methodological approaches used in this study have permitted to visualize immunocytochemically the gonadotropic hormones not only at the sites of their storage but also along the intracellular pathway of the secretory material, i.e., at the site of its synthesis and during its passage via the Golgi zone.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 196
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 171-180 
    ISSN: 1432-0878
    Schlagwort(e): Immunocytochemistry ; Ultrastructure ; Supraoptic nucleus ; Neuropil ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The neuropil located ventral to the SON was investigated by the use of immunoperoxidase staining for neurophysins, oxytocin and vasopressin, and electron miroscopy. The study was performed in six groups of rats: 1) control; 2) infusion of isotonic saline into the CSF; 3) infusion of hypertonic saline into the CSF; 4) drinking hypertonic saline for 4 days; 5) same as group 4 but injection of colchicine into the CSF on second day of dehydration; 6) salt loading for 3 months. In the control rats the ventral neuropil contained a few immunoreactive processes, the general morphology of which was completely different from that of the neurosecretory axons emerging from the SON at its dorsal aspect. In rats of groups 3 to 6 the ventral processes (VP) became loaded with neurosecretory granules, whereas the perikarya and axons were depleted. Based on their general morphology and reactivity pattern it is suggested that the VP are dendrites. Most of these “dendrites” were embedded in a glial cushion formed by the processes of a particular type of marginal glia. Some of these “dendrites” enveloped an arteriole penetrating the optic tract. All VP were rich in synaptic contacts. The possibility that the VP of neurosecretory cells may be functionally related to the subarachnoid CSF and the arteriolar blood flow is discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 197
    ISSN: 1432-0878
    Schlagwort(e): ACTH cells ; Immunocytochemistry ; Morphometry ; Spontaneous hypertension
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary ACTH-immunoreactive cells in the anterior pituitary of 4-week-old spontaneously hypertensive rats (SHR) were studied with immunocytochemical and morphometric techniques. The results were compared with data from age-matched normotensive Wistar-Kyoto rats (WKY). No significant differences were found in volume density and average size of ACTH-immunoreactive cells between these two strains. However, SHR showed a significantly larger anterior lobe (2 P 〈 0.01) than WKY, indicating that the total number of ACTH-immunoreactive cells in the anterior pituitary is greater in SHR than in WKY. These data are in agreement with radioimmunological determinations showing a significantly elevated content (2 P 〈 0.01) but only a moderately higher concentration (0.05 〈 2 P 〈 0.10) of ACTH in the anterior pituitary of SHR as compared to WKY. The present results suggest an enhanced availability of ACTH in the anterior pituitary of 4-week-old SHR, a fact which could explain the markedly enhanced stress-induced release of ACTH previously found in these animals. This study further supports the hypothesis that, among other factors, an instability of the hypothalamo-pituitary-adrenal axis may contribute to the development of genetically programmed hypertension.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 198
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 517-525 
    ISSN: 1432-0878
    Schlagwort(e): Bone marrow ; Actin ; Cell motility ; Immunocytochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary Blood cells proliferate extravascularly in the bone marrow and enter the circulation by migrating through endothelial cells of venous blood sinuses. This migration, or diapedesis, was suspected to involve actin. To test for the presence and distribution of actin, sections of rat bone marrow were examined by indirect immunocytochemistry. Affinity purified rabbit antichicken gizzard actin antibody, and goat-antirabbit IgG-FITC, or goat antirabbit IgG colloidal gold probes were used. The migrating cell contacts the endothelial cell and forms a podosome (a cortical bleb). Immunocytochemistry shows this region to contain actin. As diapedesis proceeds the podosome deforms, then breaches the endothelial cell. At this time the anterior portion of the leukocyte shows heavy labeling for actin. When the migratory cell traverses approximately half of its length through the endothelial cell, actin appears prominent in the caudal region of the cell. The immunocytochemical data suggest that actin is nonrandomly distributed in leukocytes undergoing diapedesis and may be a component of the force-generating mechanism responsible for this transcellular migratory event.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 199
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 236 (1984), S. 561-566 
    ISSN: 1432-0878
    Schlagwort(e): Pituitary gland, pars intermedia ; Peptide hormones ; Dopamine ; Corticotropin-releasing hormone ; 6-Hydroxydopamine ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary When rats were injected with 6-hydroxydopamine the catecholaminergic nerve terminals in their intermediate lobes exhibited distinct signs of degeneration. Morphometric examination of the Golgi apparatus in cells of the intermediate lobe of these rats showed significant enlargement of Golgi cisternae. The release of adrenocorticotropin, β-endorphin/lipotropin and α-melanotropin from intermediate-lobe cells in vitro was measured by radioimmunoassay. The high basal peptide release was inhibited by dopamine and stimulated by methyl-isobutyl-xanthine. In contrast, γ-aminobutyric acid, serotonin, histamine and noradrenaline, or corticotropin-releasing hormone, rat hypothalamic extract and vasopressin had no or only very weak effects. These observations indicate that the synthetic apparatus of intermediate-lobe cells is constantly depressed by dopaminergic nerves. We were not able to stimulate peptide release from intermediate-lobe cells by use of the abovementioned endogenous agents.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 200
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 237 (1984), S. 169-179 
    ISSN: 1432-0878
    Schlagwort(e): Foetal pancreas ; β Cells ; Insulin ; Fasting mothers ; Morphometry ; Rat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary After maternal fasting for 72 h the pancreatic β cells of 18-day-old foetal rats show a conspicuous enrichment in secretory material, with an increase of pancreatic insulin concentration and a marked development of the rough endoplasmic reticulum and the Golgi apparatus. The morphometric analysis shows that the intracytoplasmic migration of the secretory granules is inhibited, principally inside the cell web. Consequently the number of secretory granules fused with plasma membrane decreases and this is associated with a decreased foetal plasma insulin. The difference in the ultrastructural aspect of the β cells of foetuses from fasting mothers and of foetuses from fed mothers is less conspicuous at 19 days of gestation and progressively disappears at 20 and 21 days. The modifications in ultrastructural aspect and in functional state are discussed.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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