Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The area postrema is a circumventricular organ that plays an important role in neurohumoral regulation of the circulation. We have developed a method to examine permeability and vascular responses of the microcirculation of the area postrema in vivo. A craniotomy was performed over the dorsal brain stem in anesthetized rats, and blood vessels to the area postrema were visualized with fluorescein microscopy. Extravasation of sodium fluorescein (MW, 386), but not 150 kDa (MW) fluorescein isothiocyanate-dextran, occurred in the area postrema under control conditions. There was no extravasation of fluorescein or dextran in the brain stem under control conditions. Acute hypertension produced marked disruption of the barrier to 150 kDa dextran in the area postrema, compared with minimal disruption in the brain stem. We tested the hypothesis that the area postrema has greater permeability to small molecules than the brain stem and that this permeability might be accompanied by distinctive vascular responses. Topical suffusion of adenosine and ADP produced similar dose-related dilation of arterioles to area postrema and dorsal brain stem. Topical and intravenous vasopressin produced similar dose-related constriction of vessels to area postrema and brain stem. Electron microscopy in rats demonstrated that a barrier to horseradish peroxidase, which is absent in capillaries in the area postrema, is present in arterioles that supply the area postrema.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Microcirculation of the area postrema. Permeability and vascular responses. 275 49

Forty-one-residue corticotropin-releasing factor is a physiologically significant mediator of the hypothalamic control of corticotropin secretion by the anterior pituitary gland. This releasing hormone is produced by parvicellular neurons in the hypothalamic paraventricular nucleus that project to the external zone of the median eminence. Recent immunocytochemical evidence based on work with a rabbit antiserum against rat corticotropin-releasing factor (code rC70) suggests that about half of the parvicellular corticotropin-releasing factor-containing neurons in the hypothalamic paraventricular nucleus synthesize vasopressin, another potent corticotropin secretagogue, while the rest of the cells do not. If this is indeed the case, the neurohumoral control of corticotropin release may be mediated via distinct hypothalamic effector pathways utilizing releasing hormone cocktails of varying composition. In the present study we have examined the specificity of various antisera against rat corticotropin-releasing factor in immunocytochemical staining. Male Wistar rats pretreated with colchicine were used throughout. The brain was fixed by perfusion with a Zamboni type fixative solution. Vibratome sections of the hypothalamus were immunostained with three different primary antisera (codes rC70, rCRF-3, oCRF-N) using the peroxidase-antiperoxidase or avidin-biotin complex methods. All three antisera stained cell groups previously described to be immunopositive for corticotropin-releasing factor. Most notably, however, rC70 labelled a significant number of additional cells, most readily identified in the arcuate and suprachiasmatic nuclei, as well as in the dorsolateral hypothalamic area caudal to the paraventricular nucleus.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Immunocytochemical detection of corticotropin-releasing factor: multiple cross-reactions of a widely used carboxy-terminally directed corticotropin-releasing factor antiserum (code rC70) in rat hypothalamus. 278 48

The distribution of arginine-vasopressin (AVP)-, oxytocin-, beta-endorphin (beta-EP)- and dynorphin-immunoreactive cells was examined by peroxidase-antiperoxidase (PAP) immunocytochemistry in the ovaries of Brattleboro and Long-Evans (LE) rats. The ovarian distribution of the peptide-immunoreactivity is indistinguishable between the two strains. AVP- and beta-EP-immunoreactivity is co-localized in the majority of luteal cells, and in some cells scattered in the interstitial tissue. Of the AVP/beta-EP-positive cells, 1-2% also contained immunoreactive (ir)-dynorphin. Some cells in the interstitium contained only ir-AVP (approximately 50%) or only ir-dynorphin (approximately 5%); in the corpora lutea, however, no luteal cells appeared to contain only one peptide. AVP-immunoreactivity is also present in theca cells surrounding secondary and large, antral follicles; ir-oxytocin was not observed in any ovarian cell type in the rat. These data suggest that most luteal, and some interstitial, cells in the ovary have the capacity to produce and store up to three different neuropeptides.
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PMID:Co-expression of vasopressin with beta-endorphin and dynorphin in individual cells from the ovaries of Brattleboro and Long-Evans rats: immunocytochemical studies. 287 49

In order to examine the morphological substrates for neuronal connections between cells of the hypothalamic suprachiasmatic nucleus (SCN) that contain immunoreactivity for different neurotransmitters, a double ultrastructural immunocytochemical analysis was used. For double immunostaining, the first neuroactive substance antigen was labeled with gold-substituted silver-intensified peroxidase (GSSP), which results in a granular gold deposit of high electron and light opacity. The second antigen was labeled with peroxidase and a diaminobenzidine chromagen. The GSSP reaction product greatly increased the visibility of immunoreactive structures, with both light and electron microscopy. Intensification with the GSSP method worked at all depths of thick tissue sections as determined with analysis of immunostained sections cut perpendicular to their flat surface, and with analysis of thick 80-micron sections of brain tissue into which horseradish peroxidase (HRP) has been microinjected. On a nitrocellulose dot-blot comparison of different substrates for HRP, the GSSP intensification compared favorably with tetramethylbenzidine, but unlike tetramethylbenzidine, the GSSP was stable in a wide range of buffers. In addition to diaminobenzidine, the GSSP reaction was used to intensify and stabilize both the Hanker-Yates reagent and tetramethylbenzidine on the nitrocellulose model system. Through the use of the GSSP reaction, five new synaptic relationships in the suprachiasmatic nucleus were revealed. By increasing the sensitivity of the peroxidase method by silver-gold intensification, immunoreaction product could be found in dendrites at a greater distance from the perikaryon than in nonintensified material. Because of this greater sensitivity, the neuroactive substance contained in the cell of origin of a dendrite could sometimes be identified. Boutons immunoreactive for vasopressin-associated neurophysin were found to make synaptic contact with postsynaptic dendrites that also contained vasopressin-neurophysin immunoreactivity. Similarly, boutons containing gastrin-releasing peptide immunoreactivity made synaptic contact with cells also exhibiting gastrin-releasing peptide immunoreactivity. Neurons stained with GSSP reaction product could be easily discriminated from those containing only HRP-precipitated diaminobenzidine, allowing the simultaneous use of these two markers in the same 30-micron tissue section and subsequently in ultrathin sections for electron microscopy.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Synaptic relationships between neurons containing vasopressin, gastrin-releasing peptide, vasoactive intestinal polypeptide, and glutamate decarboxylase immunoreactivity in the suprachiasmatic nucleus: dual ultrastructural immunocytochemistry with gold-substituted silver peroxidase. 287 14

The catecholaminergic innervation of vasopressin (VP) neurons in the paraventricular nucleus (PVN) of the rat was studied at the electron microscopic level by double-labeling immunocytochemistry combining the preembedding peroxidase-antiperoxidase method with the postembedding immunogold staining method. Tyrosine hydroxylase-like immunoreactive nerve terminals were found to establish synapses with neurophysin II-like immunoreactive neuronal perikarya and their processes. This provides morphological evidence for catecholaminergic control of the release of VP, at the PVN level.
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PMID:Ultrastructural demonstration of the catecholaminergic innervation of vasopressin neurons in the paraventricular nucleus of the rat by double-labeling immunocytochemistry. 289 18

PH-8P (dynorphin[1-8])-like immunoreactive neuronal perikarya, processes, and terminals located within the human hypothalamus were investigated by the avidin-biotin peroxidase complex (ABC) immunocytochemical procedure. Immunopositive neurons were distributed throughout the hypothalamus. The distributional pattern was found to be similar to that in other mammalian species by the use of antisera against dynorphin. A large number of immunoreactive neuronal perikarya were detected in the supraoptic nucleus (SON) and the magnocellular portion of the paraventricular nucleus (PVN). Their processes appeared to project to the posterior pituitary via the internal layer of the median eminence and their distribution seemed to be less dense than in other mammalian species. PH-8P and vasopressin were colocalized in the neuronal perikarya in the human SON unlike the colocalization of these peptides in the rat SON and PVN. There were a few immunoreactive terminals in the external layer of the median eminence; their immunoreactive substances may be released into the portal veins to act on anterior pituitary cells. In addition, PH-8P-like immunoreactive neurons in the human hypothalamus may project to the extrahypothalamic area.
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PMID:Immunocytochemical demonstration of dynorphin(PH-8P)-like immunoreactive elements in the human hypothalamus. 290 52

Glycoconjugates were localized by light microscopy with lectin-peroxidase conjugates and by electron microscopy with the periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP) sequence in immunocytochemically or morphologically identified cell types in rat pituitary. Lectin histochemistry demonstrated sialic acid and glycoconjugates with N-glycosidically linked oligosaccharides in gonadotrophs, thyrotrophs, and corticotrophs. Galactose penultimate to sialic acid was observed mostly in gonadotrophs. The terminal galactose-N-acetylgalactosamine disaccharide was detected in a few gonadotrophs and in a moderate number of mammotrophs. Fucose was localized in only corticotrophs with two fucose-binding lectins and in thyrotrophs with another. Several different monosaccharides were seen in glycoconjugates in melanotrophs and in Herring bodies. Melanotrophs displayed heterogeneous staining with fucose-binding lectins. A small number of nonsecretory cells were also visualized in the pars distalis by virtue of their glycogen content. PA-TCH-SP staining revealed complex carbohydrates in secretory granules and some Golgi cisternae in all types of hormone-producing cells in the pars distalis except for the somatotrophs. Melanotrophs of pars intermedia exhibited stained secretory granules and irregular dense bodies containing a stained meshwork. Corticotrophs of the pars distalis lacked the latter bodies, although they form the same glycoprotein precursor hormone as melanotrophs. Lectin conjugates and the PA-TCH-SP sequence stained some groups of secretion granules in Herring bodies, possibly representing vasopressin-containing granules as well as other cell types in the pars nervosa.
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PMID:Glycoconjugate localization with lectin and PA-TCH-SP cytochemistry in rat hypophysis. 299 73

Some patients with von Willebrand's disease do not respond to stimuli such as venous occlusion and infusion of a vasopressin analogue DDAVP. In these patients, fibrinolytic activity is not enhanced and von Willebrand's factor is not released into the blood. Skin biopsies and cryostat sections were used to study the fibrinolytic activity of skin vessels and localization of tissue plasminogen activator (t-PA) in three patients with severe form of von Willebrand's disease. On fibrin films, no fibrinolysis developed around the skin vessels of the patients; however, using specific polyclonal and monoclonal antibodies to t-PA, and peroxidase coupled specific IgG, presence of t-PA antigen was demonstrated in endothelial cells (EC) of all of them. In plasma no t-PA activity was detected either before or after venous occlusion although t-PA inhibitor activity was in a normal range. Small amounts of t-PA antigen was measured in blood by ELISA. From these results, it is concluded that in patients with severe forms of von Willebrand's disease, t-PA present in EC is not functional and can not transform plasminogen into plasmin.
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PMID:Absence of functional activity of tissue plasminogen activator in patients with severe forms of von Willebrand's disease. 311 91

This ultrastructural study demonstrates that the vasopressin immunoreactivity found in the occasional, densely stained cells in the hypothalamus of the homozygous Brattleboro rat is localized in the rough endoplasmic reticulum. 50-micron Vibratome sections were stained with anti-vasopressin serum by use of a peroxidase method with 3,3-diaminobenzidine as chromogen. The diaminobenzidine end-product has a specific capability to bind gold particles from a chloroauric acid solution and the bound gold was used to precipitate silver grains from a silver developer. The stained sections were flat embedded in resin and ultrathin sections were cut of areas containing the immuno-identified occasional cells. In these densely stained, vasopressin-immunoreactive cells of homozygous Brattleboro rats the rough endoplasmic reticulum was dilated. The lumen of the reticulum contained both end-products of diaminobenzidine and gold/silver grains, but some parts of the reticulum appeared unstained. No other cell organelles were immunostained and no secretory granules were found. In control rats, gold/silver deposits were found throughout the cytoplasm of vasopressin-immunoreactive cells. In these immunostained cells secretory granules were seen.
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PMID:Mutant vasopressin precursor in the endoplasmic reticulum of the Brattleboro rat. Ultrastructural evidence from individual "vasopressin" cells localized with the light microscope by use of a new gold/silver method for immunostain enhancement. 318 Jan 92

The kinetics of binding and endocytosis of 125I-human holotransferrin by isolated human brain capillaries was examined using this system as a model of the human blood-brain barrier (BBB). Both binding and endocytosis of the peptide by human brain capillaries was temperature-dependent and the binding was saturated by holotransferrin, but not by insulin, somatostatin, or vasopressin. Scatchard analysis of the binding reaction revealed a dissociation constant of 448 +/- 110 ng/mL (5.6 +/- 1.4 nmol/L) and a maximal binding constant (Ro) of 8.0 +/- 1.5 ng/mg protein. Thus, the affinity and capacity of the BBB transferrin receptor is within the same order of magnitude as the affinity and capacity of the BBB receptors for insulin, insulinlike growth factor-I, or insulinlike growth factor-II. The human brain capillary transferrin receptor was also detected with a mouse monoclonal antibody to the receptor using the avidin/biotin/peroxidase technique. In conclusion, these studies characterize the human BBB transferrin receptor and support the hypothesis that this receptor acts as a transport system which mediates the transcytosis of transferrin-bound iron through the brain capillary endothelial cell in man.
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PMID:Human blood-brain barrier transferrin receptor. 330 81


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