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)

1. Isolated rat kidneys were perfused at a constant pressure of 90 mmHg in a single-pass system with either a cell-free medium or a suspension of washed bovine red blood cells, free of the components of the renin-angiotensin system. In red blood cell perfused kidneys renal haemodynamics and sodium reabsorption corresponded closer to values observed in the intact rat than in cell-free perfused kidneys. 2. In red blood cell-perfused kidneys in the absence of plasma renin substrate autoregulation of renal blood flow was almost complete at pressures above 90 mmHg, provided that perfusion pressure was changed rapidly. 3. Renin release varied inversely with perfusion pressure within a pressure range from 50 to 150 mmHg; the greatest changes of renin release occurred, when perfusion pressure was reduced from 90 to 70 mmHg; maximal stimulation of renin release was observed at 50 mmHg. After reduction of perfusion pressure, renin release immediately started to rise and reached a new level within 5 min. Local reduction of perfusion pressure in small arteries and arterioles by the injection of microspheres induced a short-lasting decrease in renal plasma flow and a transient stimulation of renin release. 4. High concentrations of furosemide stimulated renin release by a direct intrarenal mechanism. 5. Isoproterenol stimulated renin release in low concentrations without a concomitant vasodilation, whereas high concentrations induced an increase in both renal plasma flow and renin release. The effects of isoproterenol were completely blocked by propranolol. 6. Sodium nitroprusside induced similar increases in renal plasma flow, as did high concentrations of isoproterenol, but only a small and slow increase in renin release was observed. 7. Angiotensin II (AII) suppressed renin release in concentrations corresponding to plasma levels measured in the intact rat independently of its vasoconstrictor effects, whereas vasopressin in antidiuretic concentrations did not affect renin release. 8. AII, AI, synthetic tetradecapeptide renin substrate (TDP), crude and purified rat plasma renin substrate induced a dose-dependent reduction in renal plasma flow. SQ 20 881, a competitive inhibitor of converting enzyme, and low doses of 1-Sar-8-Ala-AII (saralasin), a competitive antagonist of AII, did not change renal plasma flow, whereas high concentrations of saralasin had a vasoconstrictor effect on their own. 9. Saralasin inhibited the vasoconstrictor effects of AII and TDP to a similar degree. SQ 20 881 inhibited the vasoconstrictor effects of AI and purified renin substrate, but did not influence the actions of TDP and the crude renin substrate preparation. 10. From these data it is concluded, that AI is converted into AII within the kidney at a rate of 1-2%. The vasoconstriction induced by the crude renin substrate probably does not involve the AII receptors. TDP may act by itself on the AII receptors or via the direct intrarenal formation of AII...
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PMID:Regulation of renin release and intrarenal formation of angiotensin. Studies in the isolated perfused rat kidney. 98 7

Interactions of several proteins with glutathione-insulin transhydrogenase (GIT) have been investigated by determining their ability to inhibit degradation of 125I-labeled insulin catalyzed by GIT. The inhibition by every insulin analog (des-Asn-des-Ala-pork insulin, desoctapeptide-pork insulin, des-Ala-pork insulin, pork insulin, proinsulin, and guinea pig insulin) was competitive vs. competitive vs. insulin indicating that they function as alternate substrates. The insulin analogs with the least hormonal activity showed the highest potency as inhigitors of insulin degradation. Whereas native ribonuclease and lysozyme showed little or no inhibition, their scrambled forms (i.e. reduced and randomly reoxidized) showed competitive inhibition with a potency greater than that of insulin. These results suggest that the conformation of the substrate or inhibitor is probably the major factor in determining the specificity for (or binding to) the enzyme. Studies withother peptide hormones showed competitive inhibition with vasopressin and oxytocin and noncompetitive inhibition with glycagon. The inhibition with growth hormone could be either competitive or noncompetitive. The inhibition by glucagon and growth hormone (physiologic antagonists of insulin) could serve as a control mechanism to modulate the activity of enzyme. The following showed very little or no inhibition; the native and scrambled form of pepsinogen, trypsin inhibitor of beef pancreas and of lima bean, C-peptide of pork proinsulin, and heptapeptide (B23-B29) of insulin.
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PMID:Interaction of insulin analogs, glucagon, growth hormone, vasopressin, oxytocin, and scrambled forms of ribonuclease and lysozyme with glytathione-insulin transhydrogenase (thiol: protein-disulfide oxidoreductase): dependence upon conformation. 117 Aug 77

[3-beta-(2-Thienyl)-L-alanine]-8-lysine-vasopressin was synthesized by solution techniques. The partially protected heptapeptide Boc-Cys(Ec)-Tyr-Thi-Gln-Asn-Cys(Ec)-Pro (1) was synthesized in a stepwise manner using the active ester method or the dicyclohexylcarbodiimide (DCC) coupling technique mediated by 1-hydroxybenzotriazole (HBt). The protected nonapeptide amide Boc-Cys(Ec)-Tyr-Thi-Gin-Asn-Cys(Ec)-Pro-Lys(Coc)-Gly-NH2 (2) was prepared by coupling 1 with Lys(Coc)-Gly-NH2 using DCC-HBt. From 2, [3-thienylalanine]-8-lysine-vasopressin was obtained by removing the Boc-protecting groups with trifluoroacetic acid and ethylcarbamoyl (Ec) protecting groups in refluxing liquid NH3 followed by oxidative cyclization in H2O-MeOH using ICH2CH2I. Purification was effected by partition chromatography followed by gel filtration. The highly purified product possesses activities in the oxytocic, avian vasodepressor, rat pressor, and antidiuretic assays of 19.0 +/- 0.5, 87 +/- 4, 243 +/- 5, and 332 +/- 32 units/mg, respectively. Thus [3-thienylalanine]-8-lysine-vasopressin has higher oxytocic, avian vasodepressor, and antidiuretic potencies than does 8-lysine-vasopressin, whereas its pressor potency is about the same as or slightly lower than that of 8-lysine-vasopressin.
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PMID:Synthesis and some pharmacological properties of (3-beta-(2-thienyl)-L-alanine)-8-lysine-vasopressin. 117 84

The results are reported of a potentiometric and spectroscopic study of the H+ and Cu2+ complexes of Ala-Arg8-vasopressin (Ala-AVP) and oxytocin at 25 degrees C and an ionic strength of 0.10 mol dm-3 (KNO3). The coordination chemistry of oxytocin and Cu(II) has been shown to be virtually identical to that of Arg8-vasotocin, forming unusually stable complexes with four nitrogen coordination (4N complexes) below pH 7. Spectroscopic evidence suggests weak interaction between Cu(II) and the sulphur atom of the -Cys6- residue in the 2N species (pH congruent to 6) but this is absent in the 4N complex. Evidence is also presented for perturbation of electronic transitions within the aromatic ring of the Tyr residue by Cu(II). While the physiological potency of Ala-AVP is very high, its coordination chemistry differs significantly from that of Arg8-vasopressin. With Cu(II) it forms complexes of similar stability to those with tetraglycine, demonstrating that the addition of an alanyl residue to the amino-terminal of the peptide destroys the conformation which is particularly favorable for rapid 4N coordination.
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PMID:Potentiometric and spectroscopic studies of the Cu(II) complexes of Ala-Arg8-vasopressin and oxytocin: two vasopressin-like peptides. 132 87

Vasopressin and its synthetic analogs were studied for their effect on transepithelial water flux in frog urinary bladder. As compared with AVP, 1-deamino-8-D-arginine vasopressin (dDAVP) was about 40 times less effective in stimulating osmotic water flow. The vasopressin analogs obtained by modification in positions 1 and 2 were: [1-(1-mercapto-4-tert-butylcyclohexaneacetic acid)] AVP (I); [1-(1-mercapto-4-methylcyclohexaneacetic acid)]AVP (II); [1-(1-mercapto-4-methylcyclohexaneacetic acid)-2-O-methyltyrosine]AVP (III); and those modified in position 4 were: [1-(1-mercaptocyclohexaneacetic acid)-4-arginine] AVP (IV); [1-(2-mercaptopropionic acid)-4-arginine]AVP (V). Any of the above analogs did not influence basal, but antagonized vasopressin-stimulated water flux. N-terminally extended analogs of AVP: Ala-AVP (VI); Ser-Ala-AVP (VII) and Thr-Ser-Ala-AVP (VIII) stimulated osmotic water flux to the same extent in concentration 200 times higher as that of AVP. We conclude from these studies that vasopressin analogs (I-V) competitively antagonize vasopressin-stimulated hydroosmotic activity in frog urinary bladder probably at the epithelial vasotocin V1 and/or V2 receptor site. N-terminal extension of the vasopressin molecule did not influence the capacity of AVP to induce V2 receptor-mediated action, even when used at higher concentrations.
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PMID:Hydroosmotic activities of arginine-vasopressins modified either in positions 1, 2 and 4 or at N-terminal extensions. 142 81

We report the solid-phase synthesis of eight position-9-modified analogues of the potent V1-receptor antagonist of arginine-vasopressin, [1-(beta-mercapto-beta,beta-pentamethylenepropionic acid),2-O-methyltyrosine]arginine-vasopressin (d(CH2)5Tyr(Me)AVP) (1-8) and five position-9-modified analogues of the closely related beta,beta-dimethyl less potent V1 antagonist, [1-deaminopenicillamine,2-O-methyltyrosine]arginine-vasopressin (dPTyr(Me)AVP) (9-13). In d(CH2)5Tyr(Me)AVP the C-terminal Gly-NH2 was replaced by (1) ethylenediamine (Eda), (2) methylamine (NHMe), (3) Ala-NH2, (4) Val-NH2, (5) Arg-NH2, (6) Thr-NH2, (7) Gly-Eda, (8) Gly-N-butylamide (Gly-NH-Bu); in dPTyr(Me)AVP the C-terminal Gly-NH2 was replaced by (9) Ala-NH2, (10) Val-NH2, (11) Thr-NH2, (12) Arg-NH2, and (13) Tyr-NH2. All 13 analogues were tested for agonistic and antagonistic activities in in vivo rat vasopressor (V1-receptor) and rat antidiuretic (V2-receptor) assays. They exhibit no evident vasopressor agonism. All modifications in both antagonists were well-tolerated with excellent retention of V1 antagonism and striking enhancements in anti-V1/anti-V2 selectivity. With anti-V1 pA2 values of 8.75, 8.73, 8.86, and 8.78, four of the analogues of d-(CH2)5Tyr(Me)AVP (1-3 and 6) are equipotent with d(CH2)5Tyr(Me)AVP (anti-V1 pA2 = 8.62) but retain virtually none of the V2 agonism of d(CH2)5Tyr(Me)AVP. They are in fact weak V2 antagonists and strong V1 antagonists with greatly enhanced selectivity for V1 receptors relative to that of d(CH2)5Tyr(Me)AVP. With anti-V1 pA2 values respectively of 8.16, 8.05, 8.04, 8.52, and 8.25, all five analogues (9-13) of dPTyr(Me)AVP are at least as potent V1 antagonists as dPTyr(Me)AVP (pA2 = 7.96) and three of these (9, 12, 13) actually show enhanced V1 antagonism over that of dPTyr(Me)AVP. In fact, the Arg-NH2(9) analogue (12) is almost equipotent with d(CH2)5Tyr(Me)AVP. These new V1 antagonists are potentially useful as pharmacological tools for studies on the cardiovascular roles of AVP. Furthermore the analogues of dPTyr(Me)AVP may be useful in studies on the role(s) of AVP in the V1b-receptor-mediated release of ACTH from corticotrophs.
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PMID:Synthesis and some pharmacological properties of potent and selective antagonists of the vasopressor (V1-receptor) response to arginine-vasopressin. 153 Oct 76

Isolated skate (Raja erinacea) hepatocytes swollen in hypotonic media exhibited a regulatory volume decrease (RVD) that was associated with only a small increase in K+ or 86Rb+ efflux but a substantial increase in the release of taurine, an amino acid found in high concentrations in skate hepatocytes. Taurine efflux was stimulated in media made hypotonic by addition of H2O or removal of NaCl, as well as in cells swollen in isotonic media containing rapidly penetrating solutes (202 mM ethylene glycol or 202 mM additional urea substituted for 101 mM NaCl), suggesting that cell swelling rather than hyposmolarity is the stimulus for the activation of taurine release. In contrast, release of glutathione, L-[14C]alanine and other alpha-amino acids (e.g., threonine, serine, glutamate, glutamine, glycine, or valine) was unaffected by dilution with 40% H2O. Taurine efflux was not altered by replacement of extracellular Na+ with choline+ or K+ and was only slightly diminished by replacing Cl- with NO3-. Addition of 50 mM taurine or hypotaurine to the incubation media also had no effect on volume-stimulated [14C]taurine efflux, suggesting that the taurine concentration gradient across the plasma membrane is not the driving force. Volume-stimulated taurine transport was temperature sensitive, 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid inhibitable (0.5 mM), and nearly completely blocked by metabolic inhibitors (2,4-dinitrophenol, KCN, sodium azide, oligomycin, carbonyl cyanide m-chlorophenylhydrazone, and antimycin A), suggesting an active energy-dependent process. Sulfhydryl-reactive reagents (N-ethylmaleimide, diamide, iodoacetate, tert-butyl hydroperoxide, and mercury) also blocked volume-stimulated taurine efflux, whereas efflux was unaffected by Ca2+ ionophore, phorbol ester, dibutyryl-adenosine 3',5'-cyclic monophosphate, vasopressin, or pretreatment with ouabain or furosemide. N-ethylmaleimide, diamide, 2,4-dinitrophenol, and iodoacetate plus KCN also inhibited the RVD. These findings suggest that, in contrast to hepatocytes from most vertebrate species, RVD in skate hepatocytes is associated with the release of only a small fraction of intracellular K+ but a substantial fraction of intracellular taurine and perhaps other organic osmolytes. This volume-activated taurine transport mechanism is energy and sulfhydryl group dependent and is not related to the taurine concentration gradient across the skate hepatocyte plasma membrane.
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PMID:Taurine transport in skate hepatocytes. II. Volume activation, energy, and sulfhydryl dependence. 155 Feb 35

The blunting of arterial pressure increases to a variety of pressor agents or the lowering of arterial pressure in some models of hypertension following intracerebroventricular administration of an angiotensin II (AII) antagonist, has been interpreted as prima facie evidence for the involvement of the central AII system in these situations. Central administration of vasopressin or carbachol (a cholinergic agonist) produces pressor effects which have been reported to be due to an increase in the activity of the sympathetic nervous system. We now report that central administration of AII antagonists [either (Sar-1, Ile-8) AII or (Sar-1, Ala-8) AII] in rats prevents the majority (greater than 70%) of the pressor effects of intraventricular vasopressin or carbachol. These results can be interpreted in two ways. The first is that all of these pressor agents use a central angiotensinergic mechanism(s) to increase sympathetic nervous system activity. An alternative hypothesis is that centrally administered AII antagonists non-specifically inhibit sympathetic nervous system function.
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PMID:Central administration of angiotensin II receptor antagonists and arterial pressure regulation: a note of caution. 157 44

Stimulation of quiescent human fibroblasts with the peptide mitogen bradykinin (BK) led to a biphasic elevation in cellular 1,2-diacylglycerol (DAG), as estimated by either measurement of total DAG mass or [3H]arachidonate incorporation. A rapid initial transient that peaked 15 s after BK addition was followed by a decline to near basal levels then a second rise to a plateau phase during which DAG levels remained elevated for less than or equal to 45 min. The source of the initial DAG transient appeared to be primarily polyphosphoinositides as these phospholipids were rapidly hydrolyzed after BK addition. This transient correlates well temporally with previous observations of the kinetics of inositol trisphosphate accumulation and intracellular free [Ca2+] observed in the same cells. Cultures preincubated with [3H]myristic acid incorporated label predominantly into the phosphatidylcholine (PC) pool. Subsequent addition of BK under these conditions caused only a relatively slow accumulation of [3H]DAG to a plateau level, without an initial transient. Together with the observation that PC was found to decrease upon BK stimulation, these observations suggest that the late phase of DAG accumulation may involve breakdown of other phospholipids including PC. To investigate the consequences of DAG elevation we examined the phosphorylation of an acidic 80 kDa protein, whose phosphorylation is solely dependent on the activation of protein kinase C (PK-C). The 80 kDa fibroblast protein could be immunoprecipitated by an antibody to bovine brain "myristoylated and alanine-rich C-kinase substrate" (MARCKS) and phosphopeptide maps of brain and fibroblast MARCKS were similar. Stimulation of [32P]-prelabeled fibroblasts with serum, BK, vasopressin, or 12-O-tetradecanoyl phorbol acetate, but not epidermal growth factor or calcium ionophores, resulted in the rapid phosphorylation of MARCKS. With BK or serum this phosphorylation showed an initial transient peak at less than 1 min then rose again to a plateau level that was sustained for less than or equal to 45 min. Removal of BK resulted in a rapid decline in MARCKS phosphorylation. These studies show that the biphasic DAG signal in BK-stimulated human fibroblasts correlates well with the state of activation of PK-C. However, the persistent activation of PK-C does not appear to require continued high levels of Ca2+.
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PMID:Transduction of the bradykinin response in human fibroblasts: prolonged elevation of diacylglycerol level and its correlation with protein kinase C activation. 190 4

The molecular recognition hypothesis, that peptide ligands and their receptor binding sites are encoded by complementary nucleotide sequences, was tested for arginine vasopressin (AVP) and its V1 receptor. Binding of [125I] [d(CH2)5,Sar7]AVP (a selective V1 vasopressin antagonist radioligand) or [3H]AVP to rat liver plasma membranes was inhibited by peptides known to bind to V1 receptors but not by the AVP complementary peptide (Ser-Ser-Trp-Ala-Val-Leu-Glu-Val-Ala) (PVA). Rabbit anti-PVA antibodies were nonimmunoreactive with any protein in rat liver membranes or in a partially purified preparation from rat liver containing reconstitutable vasopressin binding activity. Furthermore, there was no suppression of the AVP pressor effect by PVA in vivo using a rat blood pressure bioassay. These findings do not support the hypothesis that the V1 receptor binding site is encoded by the antisense DNA strand to AVP.
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PMID:Vasopressin antisense peptide interactions with the V1 receptor. 214 98


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