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)

Recent studies have suggested that some paraventricular nucleus (PVN) neurons projected to more than one target and, thereby, perhaps coordinate some aspects of seemingly diverse functions. We have systematically investigated the existence, location, hormonal contents and functional integrity of some axon collaterals arising from PVN neurons. This was done using intracellular injections of the fluorescent dye, Lucifer Yellow, extracellular ejections of horseradish peroxidase (HRP), immunocytochemistry with antisera directed against vasopressin (VP) and oxytocin (OX) and electrophysiological analysis of synaptic activation of perifornical neurons in response to electrical stimulation of the PVN in hypothalamic slices. Each of the three morphological techniques revealed clear axon collaterals, arising in the lateral hypothalamus and generally ventrolateral to the PVN. Most branching axons appeared to have a small number of branch points, and many collaterals appeared to terminate near their parent axon. Electrical stimulation of the PVN was found to activate synaptically perifornical neurons located in the areas where the other methods revealed collaterals. Stimulation outside of the nucleus was ineffective unless current intensities were increased 10-30-fold over those applied to the PVN. We conclude that many PVN neurons, at least some of these containing OX and other VP, give rise to axons that branch in the perifornical and more ventral lateral hypothalamus, and that some of their collaterals probably terminate on neurons close to the PVN.
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PMID:Extranuclear axon collaterals of paraventricular neurons in the rat hypothalamus: intracellular staining, immunocytochemistry and electrophysiology. 298 91

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

Apical exocytosis and increased permeability are induced by antidiuretic hormone (ADH). After this, endocytosis is also induced by ADH and is associated with the decline in ADH-induced water permeability at the apical surface of the toad urinary bladder (9, 19, 20). During this process, horseradish peroxidase (HRP), a fluid phase marker, is taken up from the mucosal solution into endocytic tubules and multivesicular bodies. We now report that we can introduce from the apical (mucosal) side, a viral transmembrane protein (the G-protein of VSV) and that this protein can be retrieved as an integral membrane protein in endocytic membranes. This was demonstrated by immunoisolation of endosomal vesicles loaded with HRP using a monoclonal antibody against the cytoplasmic domain of the G-protein.
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PMID:Endosomal compartment of toad bladder epithelium. 302 45

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

The distribution of vasopressin (AVP)-containing or oxytocin (OXT)-containing neurons in the rat hypothalamus which project to the posterior pituitary was revealed by the combination of retrograde tracing of horseradish peroxidase (HRP) and immunohistochemistry. The majority of magnocellular neurons labeled with HRP were located in some of the hypothalamic nuclei, including the supraoptic nucleus and paraventricular nucleus. Many of these neurons were also immunostained by anti-AVP or anti-OXT. On the other hand, some of the immunostained neurons were not labeled with HRP in the dorso-medial and the most caudal parts of the paraventricular nucleus. These data confirmed previous reports concerning the distribution of AVP- or OXT-neurons projecting to the posterior pituitary, as a more direct visualization of both the neuropeptides and the retrogradely transported HRP in the same tissue section was attained. In addition, some of the HRP-labeled perikarya which seemed to have direct contact with the ventricular lumen were occasionally seen; its functional significance is discussed.
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PMID:The distribution of vasopressin- or oxytocin-neurons projecting to the posterior pituitary as revealed by a combination of retrograde transport of horseradish peroxidase and immunohistochemistry. 313 51

In target epithelia, a vasopressin-induced water permeability increase is accompanied by the appearance of intramembranous particle (IMP) clusters, probably representing water-permeable patches, in the apical plasma membrane of responding cells. In the collecting duct principal cell, we have previously shown that these clusters are located in clathrin-coated pits. To determine whether vasopressin induces the endocytic uptake of these membrane domains in principal cells, we have examined the uptake of horseradish peroxidase (HRP) by principal cells of normal rats, vasopressin-deficient Brattleboro rats, and vasopressin-treated Brattleboro rats, following intravenous injection of HRP. By quantitative electron microscopy, principal cells of Brattleboro homozygous rats were found to take up much less HRP into cytoplasmic vesicles than normal rats, and HRP uptake was increased to normal levels in vasopressin-treated Brattleboro rats. Many invaginating coated pits at the cell surface were loaded with HRP reaction product, indicating their participation in the observed endocytosis of HRP. We conclude that vasopressin stimulates endocytosis in collecting duct principal cells. Since we have already shown that IMP clusters are found in coated pits at the cell surface, the endocytic removal of these putative water-permeable patches from the apical membrane seems to occur via a clathrin-mediated mechanism in this tissue.
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PMID:Vasopressin stimulates endocytosis in kidney collecting duct principal cells. 316 37

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

Studies were carried out in the rat to determine if the area postrema (AP), a medullary circumventricular organ, might be involved in the control of vasopressin (VP) release. The data from this study demonstrate the existence of direct neural connections between the AP and the hypothalamic VPergic neurons of the supraoptic nucleus (SON) as showed by the retrograde tracer horseradish peroxidase (HRP). Labeled neurons were observed in the AP following HRP injections into the SON. In addition, rats with AP lesions showed an impaired ability to conserve water and concentrate their urine in response to an hypertonic NaCl load. They, also, failed to maintain sodium retention and showed an attenuation of VP release during intracellular dehydration. These findings indicate that AP plays an important role in the regulation of VP release during changes in osmotic environment and suggest that this medullary circumventricular organ is a part of central circuitry subserving salt-water balance.
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PMID:Neuroanatomical and biochemical evidence for the involvement of the area postrema in the regulation of vasopressin release in rats. 338 49

Vasopressin-immunoreactive nerve fibers were demonstrated in the cerebral pial arteries by peroxidase immunohistochemistry. In the large pial artery (proximal part of the middle cerebral artery), they ran longitudinally to the long axis of the vessel. They ran in a spiral pattern in the distal part of the middle cerebral artery. Even in small arteries, vasopressin nerve fibers were found arranged in a longitudinal fashion. The present morphological data suggest that vasopressin nerve fibers in the cerebral artery may play a role in cerebral circulation.
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PMID:Immunohistochemical demonstration of vasopressin nerve fibers in the cerebral artery. 339 19


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