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)

Systematic analysis of the hydrolysis of benzyloxycarbonyl (Cbz)-dipeptides by cathepsin A [EC 3.4.12.1] purified from rat liver lysosomes showed that multiple forms of cathepsin A preferentially cleave peptide bonds with leucine, methionine, and phenylalanine. Cbz-Met-Met, -Met-Phe, -Phe-Met, and -Phe-Ala were hydrolyzed 6 to 8 times faster than the standard substrates, Cbz-Glu-Phe and Cbz-Glu-Tyr. The pH optima of the hydrolyses were 4.6 to 5.8. Hydrolysis of peptide bonds with glycine, isoleucine, and proline was very slow, but the rate depended on the nature of the adjacent amino acids. Proteins such as albumin, cytochrome c, gamma-globulin, hemoglobin, histone, myoglobin, and myosin were scarecely degraded. Peptide hormones, such as glucagon and adrenocorticotropic hormone (ACTH) were hydrolyzed markedly with optimum pH's of 4.5 and 4.6, respectively. Angiotensin I, II, bradykinin, Lys- and Met-Lysbradykinin (kallidin and Met-kallidin), and substance P were also hydrolyzed at appreciable rates. pH optima for these peptide hormones were 5.2 to 5.6. On the other hand, insulin and its A chain, luteinizing hormone-releasing hormone (LH-RH), oxytocin and vasopressin were cleaved slowly. In the hydrolyses of glucagon and other peptides, multiple forms of rat liver lysosomal cathepsin A again showed a carboxypeptidase nature, cleaving peptide bonds sequentially from the carboxyl terminal. Almost all of the amino acids were cleaved on prolonged incubation. Vaso-activites of angiotensin II and bradykinin were rapidly lost on hydrolysis by cathepsin A. Lysosomal cathepsin C [dipeptidylaminopeptidase I, EC 3.4.14.1] also activated angiotensin II, but did not inactive bradykinin. Cathepsin A, therefore, can be regarded as one of the lysosomal angiotensinases and kinases. No distinct differences were observed between the multiple forms of cathepsin A in these hydrolyses and inactivations of peptides.
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PMID:Studies on cathepsins of rat liver lysosomes. III. Hydrolysis of peptides, and inactivation of angiotensin and bradykinin by cathepsin A. 1 61

Purified collagenase of Clostridium histolyticum was shown to cleave reduced and S-carboxamidomethylated bovine neurophysin between Cys-13 and Gly-14. The scission resulted in formation of two separable fragments: a smaller peptide arising from residues 1 through 13, and a larger peptide comprising the remainder of the residues of the protein. By dansylation procedures, the smaller peptide was shown to have amino-terminal alanine as expected from the sequence of neurophysin II, and the larger peptide had amino-terminal glycine as anticipated. These results show that collagenase indeed cleaves bovine neurophysin II in accord with the specificity postulated for that enzyme, i.e., scission between -X-Gly- in a sequence of -Pro-X-Gly-Pro-Y-. This result, obtained with a non-collagenous protein substrate, is further confirmation of the specificity of collagenase as established by its action on collagens and on synthetic oligopeptides.
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PMID:Specific cleavage of reduced and S-carboxamidomethylated neurophysin II by the collagenase of Clostridium histolyticum. 20 39

The effect of furosemide on plasma renin, vasopressin (AVP), and aldosterone concentrations was studied in 10 control and 6 nephrectomized lambs during the 1st 2 wk of life. In a separate study in 10 newborn lambs, 1-sarcosine-8-alanine-angiotensin II (saralasin acetate, 5 mug/kg per min) was infused alone for 40 min, after which furosemide 2 mg/kg i.v. was injected in association with continuing saralasin acetate infusion. Plasma renin activity increased from a mean (+/-SEM) of 21.3+/-3.4 ng/ml per h in the 10 control lambs to 39.4+/-8.2 ng/ml per h at 8 min (P < 0.001) and remained high through 120 min after furosemide. Plasma AVP and aldosterone concentrations increased from respective mean values of 2.1+/-0.4 muU/ml and 12.8+/-2.5 ng/dl to 9.8+/-2.0 muU/ml (P < 0.01) and 23.0+/-7.7 ng/dl (P < 0.05) at 35 min and 13.8+/-2.1 muU/ml and 23.0+/-4.4 ng/dl at 65 min after furosemide (each P < 0.01). There was an insignificant AVP response in the 10 lambs treated with angiotensin inhibitor: from a mean base line of 4.7+/-0.9 to 8.3+/-2.0 muU/ml at 35 min, and 7.4+/-2.0 muU/ml at 65 min after furosemide. There was no increase in AVP in the anephric lambs. The mean increment AVP response from base line in the newborn lambs without saralasin, Delta 10.8+/-2.0 muU/ml, was greater than in the lambs with saralasin, Delta4.0+/-1.9 (P < 0.05), and greater than in the anephric lambs, Delta3.3+/-2.1 muU/ml (P < 0.05). The mean blood pressure fell 6 mm Hg in the 10 control lambs (P < 0.05), 7 mm Hg in the anephric lambs (P < 0.05), and 16 mm Hg in the lambs treated with angiotensin inhibitor (P < 0.05) by 35 min after furosemide. However, the changes in plasma AVP were not related to the fall in blood pressure. These data support the view that the observed AVP response to furosemide in the newborn lamb was mediated through the renin-angiotensin system.
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PMID:Endogenous angiotensin stimulation of vasopressin in the newborn lamb. 42 54

[3-(1,4-Cyclohexadienyl)-L-alanine,8-lysine]vasopressin, otherwise known as [3-(2,5-dihydrophenylalanine),8-lysine]vasopressin or [DiHPhe3]lysine-vasopressin, has been synthesized in an attempt to utilize 2,5-dihydrophenylalanine (DiHPhe) to evaluate the contribution of aromaticity in position 3 to biological activity. The analogue has the same primary structure as lysine-vasopressin, except that two additional hydrogen atoms are present on the ring moiety of the phenylalanine residue in position 3. The key intermediate was the protected nonapeptide N-carbobenzoxy-S-benzyl-L-cysteinyl-L-tyrosyldihydrophenyl-L-alanyl-L-glutaminyl-L-asparaginyl-S-benzyl-L-cysteinyl-L-prolyl-N epsilon-tosyl-L-lysylglycinamide that was synthesized stepwise by the solid-phase technique. Deprotection with sodium in liquid ammonia was followed by sulfhydryl oxidation with I2 to give the hormone analogue. [DiHPhe3]lysine-vasopressin exhibited 125--130 units/mg of antidiuretic, 129--132 units/mg of rat pressor, and 6 units/mg of rat uterus contracting activity. To confirm the presence of DiHPhe in the analogue, an enzymatic procedure employing Aspergillus oryzae was developed that liberates in high yield the amino acid residue in position 3 of the posterior pituitary hormone structure. This study should be applicable to other biologically active peptides.
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PMID:[3-(1,4-Cyclohexadienyl)-L-alanine,8-lysine]vasopressin: synthesis and some pharmacological properties. 53 93

(8-Arginine)vasopressin, (8-arginine)vasotocin, oxytocin and oxypressin, the 'ring' derivatives pressinamide and tocinamide, and the extended-chain analogues Pro-Arg-Val-(8-arginine)vasopressin and (8-arginine)vasopressinoyl-Ala-Met-Ala-NH(2), were synthesized by the solid-phase method and purified by sequential gel filtration on Sephadex G-15 in 50% acetic acid and 0.2M-acetic acid. Controlled oxidation of the thiol groups of the reduced peptides obtained after deprotection with sodium in liquid ammonia gave rise to products that depended on the length of the peptide chain: (i) nonapeptides gave monomer and dimer species, (ii) hexapeptides produced mixtures containing higher polymers, and (iii) dodecapeptides gave predominantly monomer with some dimerized material. The evidence suggests that the presence of the acyclic tail tripeptide in the nonapeptide hormones induces a conformation in the preceding hexapeptide that favours the formation of an intramolecular disulphide bond. For (8-arginine)vasopressin, intramolecular disulphide-bond formation is enhanced by extension of the peptide chain from either the N- or the C-terminus. The possible significance of these studies to neurohypophysial hormone-prohormone relationships is discussed.
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PMID:Influence of the peptide-chain length on disulphide-bond formation in neurohypophysial hormones and analogues. 69 27

1. In hepatocytes from starved rats, vasopressin, angiotensin (angiotensin II) and oxytocin stimulated gluconeogenesis from lactate by 25--50%; minimal effective concentrations were about 0.02pM, 1 nM and 0.2 nM respectively. 2. Vasopressin and angiotensin also stimulated gluconeogenesis from alanine, pyruvate, serine and glycerol. EGTA decreased gluconeogenesis from these substrates. 3. Hormonal stimulation of gluconeogenesis from lactate was abolished in the absence of extracellular Ca2+. 4. Insulin did not prevent stimulation of gluconeogenesis by vasopressin or angiotensin. 5. The potency of the stimulatory effects of vasopressin and angiotensin on hepatic gluconeogenesis suggests they are operative in vivo. Also, the data suggest that Ca2+ plays a role in the stimulation by these hormones.
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PMID:Stimulation by vasopressin, angiotensin and oxytocin of gluconeogenesis in hepatocyte suspensions. 74 59

Neurophysin (Np) is generally found in close association with vasopressin and oxytocin in the hypothalamo-neurohypophyseal complex. Dog neurophysin I and II have been isolated from fresh and frozen posterior pituitaries. The proteins were characterized on the basis of disc electrophoresis, immunological properties, amino acid composition and partial sequence determination. The amino terminal sequence of dog Np I is Ala-Ala-Leu-Asp-Leu-Asp-Val-Arg-Gln-Cys-Leu-Pro-Cys-Gly-Pro-Gly-Gly-Gln-Gly-while that of dog Np-II is Ala-Met-Ser-Asp-Leu-Glu-Leu. The dog Np I appears to be metabolically less stable than Np II. Isotope experiments with [35S]cystine or 3H-labeled amino acids using a design of "in vitro pulse and in vitro chase" as well as "in vivo pulse and in vivo chase," added further confirmation of the capability of the hypothalamic neurosecretory cells to synthesize concomitantly precursors of Np and vasopressin. The radioactively labeled precursors were converted to Np-like protein and vasopressin, both of which were isolated.
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PMID:Biosynthesis of neurophysin proteins in the dog and their isolation. 83 May 36

The dose-response behavior on the in vitro rat uterus of analogs of oxytocin with modification at sites in the molecule which have been predicted to contribute to the binding of the peptide to the smooth muscle receptor have been studied. Dose-response curves of [7-(3,4-dehydroproline)]oxytocin, [7-glycine]oxytocin, [7-alanine]oxytocin, deamino-[7-glycine]oxytocin and [4-threonine,7-glycine]oxytocin were determined and compared with that of oxytocin. The authors found that neither the slope of the curves nor the maximal response obtained for any of the analogs differed significantly from the hormone. The uterotonic potencies of the analogs corresponded to the relative positions along the concentration axis of their dose-response curves and to their affinities as determined by their pD2 values. The authors tentatively concluded that differences in uterotonic potencies of these analogs are in fact the result of differences in their affinity for the uterine receptor. The experimental identification of position 7 of neurohypophyseal peptides as a hormone-receptor binding site corroborates such a proposed role for the side chain of this residue based on earlier conformation-activity considerations.
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PMID:Dose-response behavior on the isolated rat uterus of oxytocin analogs with modifications at binding sites. 90 47

Homogeneous porcine neurophysin III has been obtained from slightly contaminated neurophysin material by rechromatography on diethylaminoethyl-cellulose. The purified protein binds both oxytocin and lysine vasopressin. Gel filtration on a calibrated column of Sephadex G-75 gives an estimate of the molecular weight of 10,000. Amino acid analyses establish the composition Lyla8, 1/2Cys14, Val2, Met1, Ile2, Leu7, Tyr1, Phe3. The total number of amino acid residues is 95. This composition exceeds that of porcine neurophysin-I by 1 alanine and 2 arginine residues. It has an NH2-terminal alanine and the COOH-terminal sequence- Arg-Arg-Ala. Results of peptide maps, the amino acid composition of tryptic peptides, and the sequences of two small tryptic peptides suggest that porcine neurophysin III contains the entire molecule of porcine neurophysin I plus a tripeptide -Arg-Arg-Ala connected the COOH terminus. It is threfore possible that porcine neurophysin I may have been derived from porcine neurophysin III by the proteolytic removal of the last 3 or 4 amino acid residues from the COOH terminus, and that the porcine hypothalamic tissue synthesizes only two neurophysins, II and III.
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PMID:Characterization of porcine neurophysin. III. Its resemblance and possible relationship to porcine neurophysin I. 94 86

Intravenous administration of furosemide (2 mg/kg) caused intestinal vasoconstriction in various groups of pentobarbital-anesthetized cats. (Sar1, Ala 8)-angiotensin II, a specific competitive antagonist of angiotensin II, was infused 60 min after administration of furosemide, a time when the intestinal vasoconstrictor response to the diuretic was maximal or near maximal. In hypophysectomized animals, infusion of the antagonist abolished the intestinal vasoconstriction and caused a significant fall in arterial pressure even when the intestinal nerves and adrenal glands remained intact. In contrast, the antagonist had little effect when the pituitary gland remained intact. The results suggest that endogenous angiotensin and vasopressin are overlapping mechanisms which constrict the intestinal resistance vessels and support arterial pressure following furosemide-induced volume depletion. In the absence of one control system, the other compensates to maintain the responses.
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PMID:Effect of (Sar1, Ala8)-angiotensin II and hypophysectomy on the intestinal resistance vessels and blood pressure following furosemide-induced volume depletion. 95 66


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