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)

Cardiac output and regional blood flows to myocardium, gut, uterus and kidney were determined in anaesthetised female rats by a single injection of 86RbCl. The haemodynamic responses were measured at various time intervals up to 2 h after single I.V. injections of lysine-vasopressin and the following of its analogues: a) with extended peptide chains at the N-terminal (including "hormonogens") Nalpha-glycyl-glycyl-lysine-vasopressin, Nalpha-glycyl-glycyl-glycyl-arginine-vasopressin and Nalpha-D-valyl-lysine-vasopressin, b) "carba" modifications desamino-carba6-arginine-vasopressin, desamino-carba6-D-arginine8-vasopressin, desamino-carba6-ornithine8-vasopressin, desamino-dicarba-arginine-vasopressin and c) other steric alterations - desamino-D-arginine8-vasopressin and desamino-N-methylarginine8-vasopressin. Sub-pressor doses of lysine-vasopressin were followed by marked reductions in gut and uterus blood flows which reached a peak at 10 min. and had completely receded by 60 min. The presence of steric alterations in the C-terminal tripeptide of the molecule- D-arginine or N-methylarginine in sequence position 8 - practically completely eliminated vascular activity. The same was true for Nalpha-D-valyl-lysine-vasopressin. None of the latter three analogues showed any inhibitor properties to the action of lysine-vasopressin. The two hormonogens (triglycyl N-terminal extensions) had to be given in doses 10 times greater to obtain a vasoconstrictor effect in gut and uterus equivalent in amplitude to that of a lysine-vasopressin, but this effect was still present to the same degree 2 h later with the hormonogen of lysine-vasopressin, and was only starting to return to baseline values at the same time with the arginine-vasopressin hormonogen. The vascular potency of both mono-carba L-analogues was higher than that of lysine-vasopressin, and the effect was as prolonged as with the hormonogens. The dicarba analogue also showed a prolonged action, but with much reduced potency. No significant changes in renal or myocardial blood flows were observed at all. Molecular features of vasopressin smooth muscle activity were discussed, and a receptor model was proposed. It was suggested that the -S-S-, -CH2CH2-bridges in the above analogues are not directly bound in the peptide-receptor complex and constitute the limiting factor determining complex duration, or persistence of the active peptide in the "receptor compartment". These results provide an experimental basis for possible clinical application of triglycyl-vasopressin and carba-vasopressin in bleeding from both gut and uterus and for induction of menstruation.
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PMID:Regional and systemic haemodynamic effects of some vasopressins: structural features of the hormone which prolong activity. 16 85

The following examinations, including the estimation of urinary neutral steroid metabolites, plasma cortisol, the percentage of unbound-cortisol, cortisol production rate, plasma adrenocorticotrophin (ACTH), dexamethasone suppression test, ACTH stimulation test, metopirone test, lysine-vasopressin (LVP) test and insulin tolerance test, were conducted in 16 patients with Cushing's syndrome for the presence of hypercoticism and for identifying the cause of this syndrome. Of these tests, the measurements of plasma cortisol late in the day and single dose dexamethasone suppression test were most useful for the diagnosis of hypercorticism because of their reliability and simplicity. Urinary 17-KGS, THF/THE ratio, cortisol production rate and low dose dexamethasone suppression test were also useful, whereas insulin test and LVP test were less valuable for this purpose. For the identification of the causes of this syndrome, lysine vasopressin test and metopirone test were most reliable, and plasma ACTH was also useful for this purpose, whereas insulin test and ACTH stimulation test were less valuable.
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PMID:The diagnostic value of hypothalamic-pituitary-adrenocortical function tests in patients with Cushing's syndrome. 16 71

Adenylate cyclase and the [8-lysine]vasopressin receptor were solubilized from pig kidney medulla membranes using the nonionic detergent Triton X-100. Optimal conditions for solubilization were under continuous stirring in a medium containing 0.5% (/v) Triton X-100, 100 mM Tris-HCl, pH 8, and 10 mM MgCl2. Both adenylate cyclase activity and [3H][8-lysine]vasopressin binding activity were recovered in a -26,000 X g supernatant of detergent-treated membranes. The yield of solubilized adenylate cyclase was nearly 100%. The soluble enzyme was no longer sensitive to antidiuretic hormone but was slightly activated by sodium fluoride. The affinity of the soluble receptor for [8-lysine]vasopresin was les than that of the membrane-bound receptor (mean apparent Km values, respectively 10(-7) M and 2 X 10(-8) M), however binding cooperativity was preserved. Hill coefficients were 1.42 for the soluble receptor and 1.50 for the membrane receptor. The soluble receptor discriminated as efficiently as did the membrane receptor between [8-lysine-a1vasopressin and oxytocin. The yield of spolubilized receptor was only 30% despite the fact that all binding activity had disappeared from the residual pellet of detergent-treated membranes. When the membranous receptors were occupied before solubilization and the latter was performed under conditions in which dissociation of the hormone-receptor comples is slow, i.e. at low temperature, 65% to 100% of the hormone-receptor complex was recovered in the soluble fraction. The soluble hormone-receptor complex partially dissociated on rewarming whereas the free hormone concentration was kept unchanged in the medium. The residual binding capacity, which was 30% of the initial value, was identical with that determined when the receptor was solubilized in free form before incubation with labeled hormone. It was concluded that (a) solubilization of the receptor molecules was complete, (b) during solubilization two forms of the receptor appear, of which only one is accessible to the hormone, (c) occupancy of the receptor by the hormone prevented the formation of the nonaccessible form, and (d) some component or components of the soluble fraction might be responsible for the loss in apparent affinity.
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PMID:Solubilization of the [8-lysine]vasopressin receptor and adenylate cyclase from pig kidney plasma membranes. 17 Feb 74

Simultaneous measurements of both beta-melanocyte stimulating hormone (beta-MSH) and adrenocorticotropic hormone (ACTH) in extracted plasma were performed by specific radioimmunoassays. During insulin-induced hypoglycemia, there was a marked increase of plasma ACTH levels and a slight but significant increase of plasma beta-MSH levels. Lysine-vasopressin on the other hand, caused a significant rise of plasma ACTH levels without corresponding response of plasma beta-MSH. Following glucagon administration, neither hormone rose significantly. However, metyrapone infusion caused a significant increase of both ACTH and beta-MSH levels, and frequent blood sampling revealed that both hormones were secreted episodically, and that peaks generally coincided with each other. These data suggest that the secretion of these two hormones can occur together in most instances, and that the same mechanism is involved in the secretion of both hormones under the negative feedback control.
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PMID:Plasma levels of beta-MSH and ACTH during acute stresses and metyrapone administration in man. 17 35

Vasopressin-sensitive pig kidney adenylate cyclase is sensitive to several effectors, such as Mg2+, other divalent cations, and guanyl nucleotides. The purpose of the present study was to compare the main characteristics of adenylate cyclase activation by vasopressin, Mg2+, and GMPPNP, respectively. Mg2+ ions were shown to exert at least three different effects on adenylate cyclase. The substrate of the adenylate cyclase reaction is the Mg-ATP complex. Mg2+ interacts with an enzyme regulatory site. Finally, Mg2+ can modulate the hormonal response, with Mg2+ ions affecting the coupling function--that is, the quantitative relationship between receptor occupancy and adenylate cyclase activation. At all the magnesium concentrations tested, from 0.25 mM to 16 mM, adenylate cyclase activation was not a direct function of receptor occupancy. At low Mg2+ concentrations, adenylate cyclase activation dose-response curve to the hormone tended to be superimposable to the hormone dose-binding curve. These results suggest a role of magnesium at the coupling step between the hormone-receptor complex and adenylate cyclase response. Cobalt, but not calcium, ions could exert the same effects as Mg2+ ions on this coupling step. GMPPNP induced considerable adenylate cyclase activation (15 to 35 times the basal value). Activation by GMPPNP was highly time and temperature dependent. At 30 degrees C, a 20 to 60 min preincubation period in the presence of GMPPNP was needed to obtain maximal activation. The higher the dose of GMPPNP in the medium, the longer it took to reach equilibrium. At 15 degrees C, activation was still increasing with time after 3 hr preincubation in the presence of the nucleotide. GMPPNP was active in a 10(-8)M to 10(-5)M concentration range. Unlike the results obtained with lysine vasopressin, the kinetic characteristics of dose-dependent adenylate cyclase activation curves by GMPPNP were unaffected by varying Mg2+ concentrations except for the increase in velocity when raising Mg2+ concentration. It was not clear whether or not the activation processes by the hormone and by GMPPNP had common mechanisms.
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PMID:Vasopressin-sensitive kidney adenylate cyclase: modulation of the hormonal response. 17 20

CRF activity of synthetic vasopressins and pitressin was studied in an in vitro system of cultured rat adenohypophyseal cells using direct measurement of ACTH by radioimmunoassay. Pitressin (posterior pituitary extract) induced a dose-related secretion of ACTH whereas synthetic arginine or lysine vasopressin were devoid of CRF activity, even with the largest tested dose (4 mug/ml). No potentiation of the CRF activity of hypothalamic extract was observed with any vasopressin preparation studied. We concluded that: 1) the CRF activity of posterior pituitary extract is not due to vasopressin, and 2) the ACTH secretion induced by vasopressin administration in vivo is unlikely to be due to a direct effect of vasopressin on adenohypophyseal cells.
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PMID:Studies on the corticotrophin-releasing activity of vasopressin, using ACTH secretion by cultured rat adenohypophyseal cells. 17 90

Studies were made to test the responsiveness of dispersed pars intermedia (PI) cells to a number of secretagogues, that are known to alter ACTH release from the pars distalis (PD) in vitro. In summary, (a) incubation in high (K+), which will increase ACTH release from the PD, did not alter ACTH release from the PI; (b) a crude extract of rat hypothalamus (HE) increased ACTH release from PD and PI; (c) the effect of HE was not due to its vasopression content, since pretreatment of the extract with thioglycolic acid did not modify its ACTH-releasing activity and neither lysine nor arginine vasopressin stimulated ACTH release from the PI; and (d) a partially purified CRF preparation, which will stimulate ACTH release from the PD, did not alter ACTH release from the PI. We conclude that the hypothalamus contains a substance(s) that will stimulate ACTH release from the PI and that the 'secretagogue' is neither vasopressin nor the same CRF that will stimulate ACTH release from the PD.
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PMID:In vitro release of ACTH from dispersed rat pars intermedia cells. I. Effect of secretagogues. 18 Apr 46

The effect of metergoline, a specific antiserotoninergic drug, on ACTH secretion was investigated in 29 normal volunteers and in 4 patients with increased ACTH production (3 with Addison's disease, 1 with Cushing's disease). In 15 normal subjects, a 4-day treatment with 10 mg daily of metergoline significantly blunted the ACTH response to insulin hypoglycemia. Mean peak ACTH values before and after treatment were, respectively, 333 +/- 39.2 (SE) and 235 +/- 38.8 pg/ml (P less than 0.05). The corresponding values of plasma cortisol were 29.6 +/- 2.96 and 20.5 +/- 2.67 mug/100 ml (P less than 0.05). In contrast, metergoline failed to affect the ACTH response to lysine-vasopressin (LVP) administered iv (8 subjects studied) and im (6 subjects studied). In 3 patients suffering from Addison's disease, an appreciable although not statistically significant lowering of the plasma ACTH levels was noted during metergoline administration. The mean pre- and post-treatment values of plasma ACTH in these patients were, respectively, 1116 +/- 192.2 and 666 +/- 100.8 pg/ml, 4240 +/- 50.0 and 3398 +/- 368.0 pg/ml, and 431 +/- 44.0 and 352 +/- 23.9 pg/ml. In one patient with Cushing's disease caused by a pituitary adenoma, metergoline did not appreciably modify plasma ACTH levels. Taken together, these results lend support to the concept of a physiological stimulating effect of serotonin on ACTH secretion. Moreover, they are compatible with the view that serotonin exerts its action chiefly at the hypothalamic level while LVP promotes ACTH release by a primary action on the pituitary.
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PMID:Effect of an antiserotoninergic drug, metergoline, on the ACTH and cortisol response to insulin hypoglycemia and lysine-vasopressin in man. 18 96

1. Isoelectric focusing studies of human placental diamine oxidase showed the pI value of the active enzyme to be 6.5. This information was used in modifying the enzyme purification by incorporating column chromatography on DEAE-Sephadex with ionic strength and pH gradient elution and this, together with affinity chromatography on concanavalin A--Sepharose, gave a highly purified preparation, with a specific activity of 7.0 units/mg. 2. The enzyme gave the expected stoicheiometry with p-dimethylaminomethylbenzylamine as substrate (Keq. 2700) and also oxidized [8-arginine]vasopressin, [8-lysine]vasopressin, collagen and tropocollagen. Polyacrylamide gel slices showed identical migration of diamine-oxidizing and [8-lysine]vasopressin-oxidizing activity. 3. The molecular weight, determined by ultracentrifugation, sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, variable polyacrylamide-gel electrophoresis and Sephadex G-200 column chromatography, was estimated to be approx. 70000. 4. E.s.r. spectroscopy showed that copper and manganese were present in the purified enzyme. This result was confirmed by atomic absorption spectroscopy, which indicated a stoicheiometry for copper and manganese of approx. 1.0 and 1.2g-atom respectively/70000mol.wt. unit. 5. The e.s.r. spectral intensity did not decrease nor did the spectral line shape change when excess of p-dimethylaminomethylbenzylamine was added to the enzyme. 6. Addition of K13CN to the enzyme eliminated the copper e.s.r. signal without affecting the manganese signal. 7. The placental enzyme therefore appears to differ from other amine oxidases in terms of its metal cofactor requirement, molecular weight and substrate specificity, and possible roles in vivo for this enzyme are discussed.
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PMID:Human placental diamine oxidase. Improved purification and characterization of a copper- and manganese-containing amine oxidase with novel substrate specificity. 18 34

A comparative study was performed on the plasma 11-hydroxycorticosteroids (11-OHCS) responses to lysine-8-vasopressin (LVP) before and during ingestion of an oral contraceptive wieh oestrogenic activity. A total of 19 healthy women with a normal menstrual cycle and normal plasma 11-OHCS content in blood samples at 8 a.m. and 4 p.m. were included in the study. The results show that the mean response of plasma 11-OHCS to the administration of LVP was equal in magnitude before and during ingestion of the contraceptive, although the baseline value of 11-OHCS doubled as a result of the treatment. On the other hand, during contraceptive treatment the increase of plasma 11-OHCS concentration after the administration of LVP was somewhat slower, reaching its peak later than before treatment. The noticeable variation in individual responses of plasma 11-OHCS to LVP increased during the treatment. Three subjects showed weak responses to LVP, although the adrenocortical responses to exogenous ACTH were quite normal. The inidvidual responses to LVP before and during ingestion of an oral contraceptive with oestrogenic activity are discussed.
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PMID:Effect of an oral contraceptive on the lysine-8-vasopressin test in the diagnostic evaluation of pituitary function. 18 34


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