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 presence of several naturally occurring amino acids in the serosal bath of toad urinary bladder significantly alters the hydrosmotic response of this tissue to vasopressin. We found that histidine, glutamate, and lysine increase vasopressin-stimulated water flow by 75%, 60%, and 43%, respectively. In contrast, alanine did not alter vasopressin-stimulated water flow, whereas glutamine decreased it by 25%. The effect of each amino acid represents intracellular events because their effects on theophylline-stimulated water flow were similar to those found with vasopressin. However, the site of action of amino acids varied, with some operating at steps before and others at steps after cyclic AMP generation. The fact that the metabolically inactive D-histidine and D-glutamate are as effective as their metabolically active L-counterparts suggests that the action of amino acids depends upon some physicochemical properties of their molecules. The ability of amino acids to influence the hydrosmotic effects of vasopressin was shown to be independent of prostaglandin generation, ionic composition, and molecular charge. In the case of histidine, we were able to obtain some understanding of the mechanism responsible for its action. We first showed that the effect of histidine does not depend upon its metabolism. In addition to D-histidine being as effective as the metabolically active L-histidine, we also showed that histidine is effective when its metabolism is abolished by low ambient temperature and also when its incorporation into proteins was prevented by cycloheximide. These findings suggest that histidine operates through some physicochemical property localized on its molecule. We were able to show that this property resides on the imidazole part of histidine. Imidazole, similar to histidine, increases vasopressin-stimulated water flow. Methylation of histidine on the imidazole ring completely abolished its effectiveness in increasing vasopressin-stimulated water flow. In contrast, methylation of histidine at the side chain increased vasopressin action similar to that found for histidine. We provide evidence that the physicochemical property of the imidazole ring of histidine is that of chelating Zn++ intracellularly, and that the intracellular site of action of histidine is closely linked to microtubules formation and/or action.
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PMID:Importance of amino acids on vasopressin-stimulated water flow. 286 87

Messenger RNAs (mRNA) coding for vasoactive intestinal polypeptide (VIP), peptide histidine isoleucine (PHI), somatostatin and vasopressin were localized in the suprachiasmatic nucleus (SCN) of the rat hypothalamus using in situ hybridization histochemistry. Specific mRNA coding for each of these peptides was distributed in areas coextensive with the immunohistochemical localization of the appropriate peptide. The autoradiographic signal produced with probes to VIP and PHI created dense concentrations of silver grains over neuronal perikarya in the ventrolateral SCN, and the coextensive distribution of both VIP- and PHI-mRNAs suggests that both peptides are synthesized within the same neurons. The distribution of somatostatin-mRNA was distinct from the of VIP and PHI. Labeled neurons are observed at the interface of the two SCN subdivisions and the distribution of these neurons is identical to those shown to contain somatostatin immunoreactivity. Vasopressin-mRNA is also differentially concentrated within neurons in the dorsomedial subdivision of the SCN in an area that is coextensive with vasopressin-immunoreactive perikarya. The discrete pattern of hybridization for each of these mRNAs indicates that each of these peptides are synthesized in SCN neurons and reaffirms the differential distribution of each of these chemically defined cell populations within cytoarchitecturally distinct subdivisions of the nucleus.
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PMID:Localization of vasopressin-, vasoactive intestinal polypeptide-, peptide histidine isoleucine- and somatostatin-mRNA in rat suprachiasmatic nucleus. 289 92

I present a technique that permits evaluation of the permeability to water of the luminal membrane of the toad urinary bladder, independently of constraints to water flow imposed by the remainder of the tissue. This technique essentially depends on fixation of the luminal membrane with 1% glutaraldehyde for 5 min, and subsequent elimination of cytosolic constraints by decreasing the tonicity of the serosal bath to 1/2 normal strength. The increased hydraulic conductivity found with serosal hypotonicity is readily reversible, as the bladder returns to an isotonic serosal bath. By evaluating water flow in luminally fixed bladders during bathing in normal and hypotonic bath, one may identify the relative contribution of the luminal membrane and the "cytosol" on water flow. Using this technique, I found that the effect of the prostaglandin inhibitor Naproxen to increase vasopressin-stimulated water flow is due to increased luminal membrane permeability. The effect of histidine to increase vasopressin-stimulated water flow, however, depends on increased permeability of both the luminal membrane as well as the underlying structures. The action of serosal hypertonicity to induce water flow is due to an increased luminal permeability. However, serosal hypertonicity decreases "cytosolic" permeability, so that its overall function is a composite effect of its action at the luminal membrane and the "cytosolic" level.
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PMID:Cell determinants of vasopressin-stimulated water flow. 293 7

In an attempt to clarify the nature of histaminergic neuromodulation of the vasopressinergic system, several studies under different experimental paradigms were carried out. L-Histidine loads (8 mmol/kg, i.p.) induced a marked increase in histamine (HA) in the anterior (AHR) and posterior (PHR) hypothalamic regions, the median eminence (ME) and adenohypophysis (Ah) with no apparent effect on the concentration of HA in the neurohypophysis (Nh), as measured by high-performance liquid chromatography. These findings correlated with decreases in vasopressin (VP) levels in the AHR and ME, accompanied by increases of the neuropeptide in the PHR and Ah. Intraperitoneal injections of HA (6 mumol/kg), resulted in a significant (p less than 0.005) rise in VP levels in the PHR, ME and Ah. HA induced an elevation of VP in the prefrontal cortex (PFC) from 6.23 +/- 2.02 to 43 +/- 4.05 microU/mg, as well as a 60% reduction in neurohypophyseal VP. These HA-induced VP responses were abolished by both mepyramine (3 mumol/kg) and famotidine (4 mumol/kg) in the PHR and PFC. Mepyramine suppressed the HA-induced VP response in the Ah and enhanced it in the Nh, while famotidine did the opposite. When alpha-fluoromethylhistidine (FMH), an irreversible inhibitor of histidine decarboxylase, was administered at doses of 100 mg/kg/day (i.p.), hypothalamic HA levels fell by 40-45% after 1 h, by 50% after 3 h, and by 65-80% after 24 h in adrenalectomized rats. In the same conditions, but after a week of treatment with FMH, the VP response to adrenalectomy was clearly impaired.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Histaminergic neuromodulation of the release of vasopressin. 303 9

Addition of histidine to the serosal bath of the toad bladder increases the hydrosmotic response of vasopressin in this tissue. Because this represents primarily the effect of the imidazole ring of histidine, which is a known inhibitor of the production of prostaglandins, we evaluated whether histidine increases the response to vasopressin through decreased prostaglandin production. Histidine increases the response to vasopressin much more than 10(-5) M naproxen, even though the latter was equipotent to histidine in reducing prostaglandin E2 (PGE2) production. Furthermore, histidine was additive to naproxen in increasing the hydrosmotic effect of vasopressin, without causing a further decrease in PGE2 production. These findings suggest that histidine has an effect over and above that due to inhibition of prostaglandin synthesis. Our results suggest that histidine enhances the permeability of the tissue beneath the luminal membrane, an effect not found with naproxen. We propose that histidine increases the hydrosmotic response to vasopressin through at least two distinct mechanisms: 1) it decreases prostaglandin synthesis and thus increases luminal permeability; 2) it decreases the resistance to water movement of the tissues beneath the luminal membrane.
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PMID:Effects of histidine on vasopressin action: role of decreased prostaglandin production. 317 53

The distribution of vasoactive intestinal peptide (VIP) and peptide histidine isoleucine amide (PHI) was investigated in the canine hypothalamus by immunocytochemistry. VIP- and PHI-like immunoreactive neurons were detected in the magnocellular supraoptic and paraventricular nucleus. These magnocellular VIP- and PHI-producing neurons coexist with vasopressin-like immunoreactivity and send axons to the median eminence and neurohypophysis. These findings may serve as an anatomical basis for studying the function of VIP and PHI on pituitary hormone secretion.
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PMID:Vasoactive intestinal peptide- and peptide histidine isoleucine amide-like immunoreactivity colocalize with vasopressin-like immunoreactivity in the canine hypothalamo-neurohypophysial neuronal system. 353 28

Overhydration inhibits release of vasopressin (VP) and oxytocin (OT) from the hypothalamo-neurohypophysial system during hypovolemia. We investigated whether opioid peptides mediate the inhibitory effect of water on secretion of these hormones. Conscious male rats were made hypovolemic by hemorrhage (HEM, 0.51 ml/min) of 20 and 35% of the blood volume or by injection of either subcutaneous polyethylene glycol (PEG, 20,000 mol wt, 35 ml/kg) or intraperitoneal histamine (HIS, 15 mg/kg, 1 ml/kg). Animals were intubated orally 1-4 min (HEM, HIS) or 6.75 h (PEG) later with or without administration of water (40 ml/kg). Four to seven min after intubation rats were injected with saline (1 ml/kg) or naloxone (2 or 5 mg/kg) and then decapitated 6-10 min later. Control animals were treated similarly but were not stimulated by hypovolemia. VP and OT were extracted from plasma and quantified by radioimmunoassay. Data were analyzed by analysis of variance. In HEM animals blood pressure fell and plasma osmolality increased, both of which correlated positively with the rise in plasma [VP] and [OT]. Overhydration lowered the plasma osmolality, attenuated the fall in blood pressure, and reduced [VP] and [OT] in plasma of HEM animals. The opiate receptor antagonist, naloxone, did not alter these changes in blood pressure or plasma osmolality, or the plasma [VP] after HEM in rats treated with or without water. Plasma [OT] was, however, increased by naloxone in both normally hydrated and overhydrated rats. Thus, regardless of the hydrational state of the animal, opioid peptides inhibited release of OT but not VP during hemorrhage. Data consistent with this interpretation were also obtained from rats made hypovolemic with PEG or HIS.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Inhibition of VP and OT release by water in hypovolemia is independent of opioid peptides. 360 88

To assess the role of vasopressin (AVP) in congestive heart failure (CHF), we investigated 10 patients with CHF refractory to conventional treatment, before and 60 minutes after intravenous administration of 5 micrograms/kg of d(CH2)5Tyr(Me)AVP, a specific antagonist of AVP at the vascular receptor level. Heart rate, systemic arterial pressure, pulmonary arterial pressure, pulmonary capillary wedge pressure, cardiac index by thermodilution, and cutaneous blood flow by laser-Doppler technique were measured. In 9 patients there was no significant hemodynamic and cutaneous blood flow response to the AVP antagonist. Plasma AVP was 2.3 +/- 0.8 pg/ml and plasma osmolality 284 +/- 14 mosm/kg H2O. The tenth patient had the most severe CHF. His plasma AVP was 55 pg/ml and plasma osmolality 290 mosm/kg. He responded to the AVP antagonist with a marked decrease in systemic arterial pressure from 115/61 to 79/41 mm Hg, in pulmonary arterial pressure from 58/31 to 33/13 mm Hg and in pulmonary capillary wedge pressure from 28 to 15 mm Hg. Simultaneously cardiac index increased from 1.1 to 2.21 X min-1 X m-2 and cutaneous blood flow rose 5-fold. Thus, most patients with CHF have only moderately elevated plasma AVP and its role in determining peripheral vascular resistance appears to be limited. AVP may become important in rare patients presenting with marked hemodynamic instability and very high plasma AVP.
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PMID:[Hemodynamic effects of an inhibitor of the vascular effects of vasopressin in patients with congestive heart failure]. 384 12

An oxytocin/bovine neurophysin I biosynthetic precursor, [N epsilon-diacetimidyl-30,71, des-His106]pro-OT/BNPI, was synthesized from a synthetic oxytocinyl peptide, 1/2Cys-Tyr-Ile-Gln-Asn-1/2Cys-Pro-Leu-Gly-Gly-Lys-Arg, and native neurophysin by chemical semisynthesis. The semisynthetic precursor contains the entire sequence of the biosynthetic precursor deduced from the complementary DNA structure except for omission of the carboxyl-terminal histidine residue. The covalent structure of the semisynthetic product was verified by amino acid analysis and amino-terminal analysis. Analytical affinity chromatography was employed to evaluate noncovalent binding properties of the precursor. The precursor does not bind significantly to immobilized Met-Tyr-Phe, a hormone binding site ligand. In contrast, the acetimidated precursor binds to immobilized bovine neurophysin II, with a 13-fold higher affinity than does acetimidated neurophysin itself. When a hormonal ligand, [Lys8]vasopressin, was added to the elution buffer at the concentration of 0.1 mM so that a major portion of the immobilized BNPII was liganded, the affinity between the immobilized liganded BNPII and the precursor was enhanced 8-fold and approached the affinity for the liganded (bovine neurophysin I-immobilized BNPII) interaction. The data imply that the precursor can self-associate and that this self-association is closely related to that of liganded neurophysin. The tripeptide affinity matrix data argue that, in the precursor, the ligand binding site of the neurophysin domain is occupied intramolecularly by the hormone domain. The data verify the view that both the self-association surface and hormone binding site are established upon precursor folding. A disulfide stability analysis showed the resistance, to disulfide interchange by dithiothreitol, of semisynthetic precursor but not of neurophysin, as judged by protein association and peptide ligand binding activities, respectively. The results argue that the molecular structure of the precursor is established upon precursor folding and before enzymatic processing that produces mature hormone and neurophysin.
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PMID:Molecular properties of the oxytocin/bovine neurophysin biosynthetic precursor. Studies using a semisynthetic precursor. 400 99

1. Three neurophysins, proteins that bind the polypeptide hormones oxytocin and vasopressin, have been isolated from acetone-dried porcine posterior pituitary lobes. The proteins have been named porcine neurophysins-I, -II and -III in order of their electrophoretic mobilities at pH8.1. 2. Electrophoretic comparison of the purified proteins, which are homogeneous on starch-gel electrophoresis, with the soluble proteins of fresh porcine posterior pituitary lobes extracted in 0.1m-HCl and in buffer pH8.1 suggests that the isolated proteins are native to the fresh tissue. 3. Neurophysins-I and -II are present in similar amounts in the tissue, whereas neurophysin-III is present only in small quantities. Acetone-dried tissue also contains traces of other hormone-binding neurophysin components. 4. All the neurophysins can bind both oxytocin and [8-lysine]-vasopressin. 5. The apparent molecular weights of the neurophysins increase with increasing protein concentration as measured by equilibrium sedimentation in the ultracentrifuge. 6. Neurophysins-I and -III are of similar molecular dimensions, contain one residue of methionine per molecule and lack histidine. The minimum molecular weight of neurophysin-I obtained by amino acid analysis is 9360. Neurophysin-II is of larger molecular dimensions than neurophysins-I and -III and can be separated from these by gel filtration on Sephadex G-75. It contains no histidine or methionine, and its minimum molecular weight has been estimated as 14020 by amino acid analysis. 7. Each of the three neurophysins possesses N-terminal alanine. 8. The possible biological significance of the existence of several neurophysins within one species is discussed.
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PMID:The isolation of three neurophysins from porcine posterior pituitary lobes. 544 78


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