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 aim of the emergency management of bleeding varices is to stop the hemorrhage nonoperatively if possible, avoiding emergency shunt surgery, an operation that has a higher mortality than elective shunt surgery. Patients with an upper gastrointestinal hemorrhage should undergo endoscopy immediately to verify the diagnosis of bleeding varices. They can then be categorized according to whether they stop bleeding spontaneously (group 1), continue to bleed slowly (group 2) or continue to bleed rapidly (group 3). Group 1 patients are discussed in the second part of this two-part series. Group 2 patients are initially treated with vasopressin given intravenously; those who fail to respond should undergo emergency angiography and receive vasopressin intra-arterially. If this fails, patients at low surgical risk should undergo urgent shunt surgery; those at high risk do better with endoscopic sclerotherapy. Group 3 patients are also given an intravenous infusion of vasopressin. Patients at low surgical risk who continue to bleed then receive tamponade with a Sengstaken--Blakemore tube. If this fails, they undergo emergency creation of an H-shaped mesocaval shunt. Patients at high surgical risk who fail to respond to vasopressin given intravenously are next treated intra-arterially. If this fails they are given either endoscopic or transhepatic sclerotherapy.
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PMID:Bleeding varices: 1. Emergency management. 700 79

Sixty patients with active upper gastrointestinal bleeding were randomized to received either continuous intravenous infusions of vasopressin (29 patients) or placebo (31 patients) at a rate of 40 U/h. Six hours after beginning the study, 13 patients in the vasopressin group and 11 in the placebo group] had ceased bleeding (p = 0.46). By 24 hours. 17 patients in the vasopressin group and 14 in the placebo group had stopped bleeding (p = 0.30). Restriction of the analysis to patients bleeding from varices showed no advantage with vasopressin treatment after 6 or 24 hours. No consistent trend favoring use of vasopressin to stop hemorrhage was noted during the 30-month study period. There was little difference between the two groups in the number of patients needing surgery (13 on vasopressin, 18 on placebo; p = 0.30) or the number of deaths (eight on vasopressin, 11 on placebo; p = 0.51); the transfusion requirement was the same. In our patients, a continuous intravenous infusion of vasopressin neither controlled bleeding nor altered outcome.
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PMID:Continuous intravenous vasopressin in active upper gastrointestinal bleeding. 704 28

The distribution of fluorescent varicosities in the supraoptic nucleus of Brattleboro rats was compared to that in normal rats. The Brattleboro rat, which is characterized by a genetic absence of vasopressin, had fewer fluorescent varicosities in apposition to the vasopressin-deficient perikarya. The oxytocin-producing neurons in the same nucleus were hyperinnervated. These data suggest that the target neuron peptide (vasopressin) is necessary for the maintenance of normal noradrenergic innervation patterns.
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PMID:Supraoptic nucleus of the Brattleboro rat has an altered afferent noradrenergic input. 705 81

Evidence is presented indicating that norepinephrine (NE) inhibits vasopressin (VP) release from the rat hypothalamo-neurohypophyseal explant under some, but not all, conditions in vitro. NE at 10(-5) M inhibited basal VP release and inhibited acetylcholine-induced release in a concentration-dependent fashion. However, the induction of VP release caused by the addition of NaCl (sufficient to yield a 10 mosmol/kg H2O increase in culture medium osmolality) was not reduced by NE in concentrations as high as 10(-5) M. An alpha-adrenergic receptor mediation of the inhibition of VP release by NE was suggested by the ability of phentolamine and phenoxybenzamine, but not propranolol, to block this effect. In addition, phentolamine at 10(-4) M, but not equimolar amounts of propranolol, increased VP release when added alone on day 2 of culture, but not on days 3 or 4. Histofluorescence examination of additional explants revealed that endogenous catecholamine was still present on day 2 within varicosities in the supraoptic nucleus, but diminished by days 3 and 4, suggesting that endogenous NE could influence basal VP release. The results indicate that NE can inhibit spontaneous and cholinergically stimulated VP release from the hypothalamo-neurohypophyseal explant, but osmotic stimulation renders the explants insensitive to attenuation of VP release by NE.
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PMID:Characterization of noradrenergic control of vasopressin release by the organ-cultured rat hypothalamo-neurohypophyseal system. 708 15

Angiography is of value in the diagnosis and interventional therapy of diffuse hepatocellular disease. Hepatic arteriography is the primary diagnostic method; hepatic venography, portal venography, transvenous liver biopsy and direct cholangiography are complementary. They allow the assessment of type and stage of diseases, their hemodynamic consequences and permit the differentiation of diffuse diseases from tumorous processi. Selective vasopressin infusion and transhepatic catheter obliteration of varices are interventional techniques used to control massive bleeding from gastroesophageal varices--one of the most serious complications of diffuse hepatocellular diseases.
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PMID:Angiography in diagnosis and therapy of diffuse hepatocellular disease. 739 83

Management of variceal hemorrhage is complex and can be difficult. Initially, the severity of the bleeding episode must be assessed and the intravascular volume repleted. Several treatment options are available. A trial of pharmacologic therapy (eg, vasopressin) may control acute bleeding. Temporary balloon tamponade of varices is helpful if bleeding continues. Endoscopic sclerotherapy and variceal ligation appear to be equally beneficial, although fewer complications have been reported with the latter. Transjugular intrahepatic portacaval shunt (TIPS) and portal-systemic shunt surgery are alternatives when endoscopic therapy fails; TIPS is preferred in patients awaiting liver transplantation. Ultimately, the choice of treatment is based on the expertise available at each medical center.
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PMID:Variceal bleeding. What are the treatment options? 750 75

Drug therapy for acute variceal bleeding should be viewed as an adjunct to emergency sclerotherapy. Its role in preventing very early rebleeding (within days) following sclerotherapy needs to be established. The best candidates for such a role are somatostatin and octreotide, but glypressin and vasopressin and nitroglycerin combinations have therapeutic effects in the short-term. Propranolol is the drug for long-term prevention of rebleeding and prevention of the first variceal bleed. For primary prophylaxis it significantly reduces the rate of bleeding, and there is a trend towards reducing mortality. It should be used in cirrhotic patients with large varices. For secondary prophylaxis, propranolol significantly reduces rebleeding but does not improve survival. The reduction in rebleeding is similar to long-term sclerotherapy when compared in randomized studies. There is no value in adding beta-blockers to sclerotherapy compared with sclerotherapy alone, but few studies have evaluated the effects after the eradication of varices. beta-Blockers can be used as the first-line therapy to prevent variceal rebleeding. They also have been shown to reduce the frequency of rebleeding from congestive gastropathy. Many patients do not have a portal pressure reduction with propranolol. The addition of isosorbide mononitrate converts many nonresponders to responders. Current clinical trials are evaluating if therapeutic efficacy is improved by these drug combinations.
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PMID:Pharmacological therapy for portal hypertension: rationale and results. 755 72

Magnocellular perikarya within the retrochiasmatic division of the supraoptic nucleus of bovine and porcine hypothalami were immunoreactive (ir) with antiserum against tyrosine hydroxylase (TH), but not dopamine-beta-hydroxylase (DBH). Few cells in this region were also immunoreactive for vasopressin (VP) or oxytocin (OT). In contrast, the main division of the supraoptic nucleus contained numerous perikarya immunoreactive for VP and OT, but not TH nor DBH. Both the retrochiasmatic and principal divisions of the supraoptic nuclei contained TH- and DBH-ir fibers and varicosities. This region in bovine and porcine hypothalami corresponds to the ventral A15 catecholaminergic (dopamine-producing) cell group.
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PMID:Catecholaminergic region A15 in the bovine and porcine hypothalamus. 762 Sep 7

Using a biotin-streptavidin-horseradish peroxidase (HRP) immunohistochemical technique the distribution of substance P-immunoreactive neuronal elements was investigated in the rat suprachiasmatic nucleus (SCN). Substance P-immunoreactive nerve fibres and varicosities were distributed throughout the suprachiasmatic nucleus, with the largest accumulation in its ventral part. Because this location overlaps with the innervation of retinal afferents, the distribution and density of substance P-immunoreactive fibres in bilaterally enucleated rats were compared to normal rats. The density of substance P-immunoreactive fibres and nerve terminals in the ventral part of the suprachiasmatic nuclei was reduced in the rats with bilateral destruction of the optic nerves, whereas the density of fibres and nerve terminals in the dorsal part as well as other retinal target areas in the thalamus and mesencephalon was unaffected. In rats pretreated with an intraventricular injection of colchicine several substance P-immunoreactive perikarya were identified in the suprachiasmatic nucleus. The immunoreactive neurons, measuring 9.7 microns +/- 1.1 microns in diameter, were frequently observed in the central core of the nucleus and to a lesser extent in the dorsomedial and ventrolateral subparts. Using in situ hybridization histochemistry pre-protachykinin-A mRNA was found in the same part of the SCN indicating that synthesis of substance P takes place in SCN neurons. Using a double immunohistochemical approach applying diaminobenzidine and benzidinedihydrochloride as chromagens substance P-, vasoactive intestinal peptide (VIP)-, and vasopressin/neurophysin-immunoreactivities were identified in the same brain section. The substance P-immunoreactive perikarya constituted a separate population of SCN neurons, which were not vasopressin-, neurophysin- or VIP-immunoreactive. Taken together, these observations show that substance P is contained in the retinohypothalamic pathway and within a group of SCN cell bodies, indicating that substance P may play a role in the generation and entrainment of circadian rhythmicity.
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PMID:Substance P in the suprachiasmatic nucleus of the rat: an immunohistochemical and in situ hybridization study. 769 27

Catecholaminergic fibers in the suprachiasmatic nucleus of adult rats were investigated by use of light- and electron-microscopic immunocytochemistry. The suprachiasmatic nucleus receives a modest density of tyrosine hydroxylase-containing axons, homogeneously distributed in the nucleus and forming varicosities throughout its entire rostro-caudal extension. Immunolabeling with antibodies against dopamine showed that this catecholamine input comprises a dopaminergic component. Many tyrosine hydroxylase-positive cells were localized at the immediate periphery of the suprachiasmatic nucleus. With electron-microscopic examination, dendrites of these neurons were found within the limits of the nucleus as well as at a border zone between the suprachiasmatic nucleus proper and the optic tract where they received unlabeled synapses, providing a morphological support for a possible role of dopaminergic neurons in the integration and/or transfer of light-related signals. More than 91% of catecholaminergic axonal varicosities were found to establish morphologically defined synapses with dendrites. To investigate whether these synapses might be shared with neurons of one or both of the two main peptidergic populations of the nucleus, namely vasoactive intestinal peptide- and vasopressin-containing neurons, we carried out double-labelling experiments combining immunoperoxidase and immunogold-silver labeling. Results showed only a few cases of direct association of the catecholaminergic terminals with these peptidergic categories. In both types of dually stained sections, catecholaminergic synapses were preferentially made with unlabeled dendrites. The homogeneous distribution of tyrosine hydroxylase-immunoreactive fibers in the suprachiasmatic nucleus could therefore reflect a lack of significant catecholaminergic innervation of both vasoactive intestinal peptide- and vasopressin-synthesizing neurons.
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PMID:Catecholaminergic innervation of the suprachiasmatic nucleus in the adult rat: ultrastructural relationships with neurons containing vasoactive intestinal peptide or vasopressin. 775 Jan 39


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