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)

Changes in rheological properties of the blood were produced by intravenous injection of a high-molecular weight dextran and lysin-vasopressin. The animals were decapitated in one hour. Oxygen absorption by mitochondria of the heart in oxidation of 2.5-10 mM of the succinate increased by 90-120%, as compared to control. Stimulation of respiration by ADP was decreased 1.5-2 times. Simultaneous administration of the succinate and glutamic acid normalized the respiration and phosphorylation. A possibility of inhibition of succinic-dehydrogenase by the oxalo-acetic acid was suggested. Switching of respiration to succinic acid and limiting of the SDG activity can be considered as adaptive factors under conditions of changes in rheological properties of the blood, and are directed to the maintenance of cardiac activity, this being evidenced by the absence of changes in the ATP-asic activity and in the myosin content of the heart.
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PMID:[The influence of rheologic properties of the blood on adaptive processes in the myocardium]. 12

beta-Lipotropin is the predominant opioid peptide of the human pituitary and rat pars distalis and is present in concentrations essentially equimolar with corticotropin. When freshly, obtained nonfrozen rat anterior pituitaries were homogenized with 0.2 M HCl, approximately 98% of the immunoreactivity detected utilizing an antiserum that crossreacts equally with beta-lipotropin and beta-endorphin coeluted with 125I-labeled human beta-lipotropin upon molecular sieve chromatography. The remainder of the activity eluted with synthetic human beta-endorphin. Similar results were obtained for human pituitary. HCl homogenization of thawed tissue or homogenization of fresh tissue with acetic acid yielded substantially greater concentrations of beta-endorphin and decreased concentrations of beta-lipotropin. In human subjects, acute anterior pituitary stimulation using either insulin-induced hypoglycemia or vasopressin administration was associated with increased plasma beta-lipotropin and corticotropin levels. At the time of peak concentrations, no significant levels of beta-endorphin were detectable. These data indicate the lack of significant amounts of beta-endorphin in human pituitary. Additionally, there appears to be no specific intrapituitary conversion of beta-lipotropin to beta-endorphin.
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PMID:beta-Lipotropin is the major opioid-like peptide of human pituitary and rat pars distalis: lack of significant beta-endorphin. 20 78

The present report describes high yield enzymatic radio-iodination of the apical and basal-lateral plasma membranes of toad bladder epithelium, by a procedure that does not breach the functional integrity of the epithelium, as assessed by the basal and vasopressin-sensitive short-circuit current (SCC). Restriction of the label to the membrane surface, was ascertained by light and electron-microscopic autoradiographs. On the apical surface, the grains were over the glycocalyx and the plasma membrane. Analysis of the labeled glycocalyx by agarose gel filtration, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), as well as enzymatic and pH-dependent hydrolysis indicated that the glycocalyx is a trichloro-acetic acid-soluble macromolecular complex of high molecular weight composed of a peptide moiety attached to large prosthetic groups (presumably carbohydrates) by O-glycosidic bonds. Analysis of the labeled apical plasma membrane components by agarose gel filtration and SDS-PAGE disclosed the presence of six major species of apparent molecular weights: 23,000, 28,000, 37,000, 44,000, 68,000, and 95,000. More than half of the membrane-associated radio-iodine was in two bands of molecular weights 37,000 and 44,000. Concentrations of vasopressin and cyclic AMP sufficient to increase the SCC significantly did not modify the extent of membrane labeling or the distribution of the label among the apical membrane components (presumably proteins) as assessed by SDS-PAGE. Iodination in the presence of amiloride inhibited incorporation but did not change the pattern of the distribution of the label among the components resolved by SDS-PAGE. Iodination of basal-lateral plasma membranes, at a yield comparable to that obtained with apical labeling, was attained after about 30 min of exposure of the intact bladder to the labeling solutions. Approximately 25% of the basal-lateral labeling was lost when the epithelial cells were harvested after collagenase treatment, implying that some iodination of the basement membrane had taken place. Less than 10% of iodination of the apical or basal-lateral surfaces was accounted for by lipid-labeling. Analysis of the labeled apical and basal-lateral species by enzymatic digestion and thin layer chromatography disclosed that virtually all the radioactivity was present as mono-iodotyrosine (MIT).
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PMID:Radio-iodination of plasma membranes of toad bladder epithelium. 37 44

(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

An ulcer was induced in the anterior wall of the antrum by local injection of acetic acid solution. Carbonized microspheres 15 +/- 5 micrometer in diameter, labeled with 85Sr and 141Ce, were used to measure blood flow in different regions and layers of the stomach wall, and in each sample the mucosa was separated from the muscularis. The radioactivity of a blood reference sample and the tissue sample was determined, and the blood flow was calculated for each tissue sample. Two groups of anesthetized animals were used: animals with normal stomachs given vasopressin and animals with a 1-week ulcer given vasopressin. The vasopressin was administered intravenously over a 20-min period. In animals with normal stomachs and in animals with a gastric ulcer vasopressin was found to decrease the blood flow to the stomach in all areas examined. The presence of a 1-week ulcer in the cat did not seem to influence the effect of vasopressin.
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PMID:Effect of vasopressin on blood flow distribution in the stomach of cats with gastric ulcer. 72 99

Extracts of porcine hypothalamic fragments (HF) bring about the release of prolactin when injected into estrogen-progesterone pretreated male rats. To determine the extent to which this prolactin-releasing activity (PRA) is attributable to thyrotropin-releasing hormone (TRH) and/or vasopressin (VP), (both hormones capable of releasing prolactin in this preparation), PRA was assayed following destruction of TRH and VP by incubation in rat serum, and after separation on Sephadex G-25 columns. Acetic acid (2N) extracts of HF contain 22 to 27 ng TRH and 650 to 1000 ng of VP per HF as determined by immunoassay. Incubation for 1 h in fresh rat serum degraded 91 to 99% of both TRH and VP. PRA fell after incubation, but was still detectable, indicating residual activity that resisted degradation. Prolactin release responses to HF extracts and to TRH were log-dose dependent, but had different activity slopes. The minimal detected dose of TRH which released prolactin was 10 ng, while minimal effective doses of serum inactivated HF extract contained only 0.6 ng of TRH. Maximum effects with serum-inactivated HF extract were achieved with 2 HF equivalents containing 2.6 ng of TRH. More than 400 ng of TRH were required to give an equivalent PRA response. Sephadex G-25 chromatography of hypothalamic extracts using 2.0 N acetic acid separated a fraction which after treatment with serum to inactivate most TRH present caused marked prolactin release and contained only 0.7 ng of TRH and 0.3 ng of VP per dose. Evidence for a PIF was the demonstration that retarded fractions from the column significantly decreased plasma prolactin levels. The finding of PRA in hypothalamic extracts separate from both TRH and VP is evidence for the existence of a distinct prolactin-releasing factor.
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PMID:Prolactin-releasing factor (PRF) in porcine hypothalamic extract distinct from TRH. 82 45

Previous studies have indicated the existence of natriuretic factors of hormonal nature with the posterior pituitary gland as a possible site of origin. It was in this light that a series of experiments was designed to examine the posterior pituitary for such factors. Acetic acid extracts of porcine and bovine posterior pituitary lobe tissue were subjected to gel filtration on Sephadex G-25. Several fractions in the molecular size range of 1000 were obtained which possessed potent natriuretic activity as assayed in rats. The activity of these fractions maximally increased sodium excretion to 6-8 muequiv./min, a 10- to 40-fold increase above control, when administered intraperitoneally to hydropenic, conscious rats. However, oxytocin and vasopressin, present in the posterior pituitary are natriuretic. These hormones were measured by radioimmunoassay, and invariably only those fractions which contained vasopressin and (or) oxytocin possessed natriuretic activity. Moreover, the extent of the natriuresis could be accounted for by the vasopressin and (or) oxytocin content of the test fractions. The natriuretic property of this material was abolished by treatment with thioglycollate. Further purification of natriuretic fractions by ion exchange resins, thin-layer chromatography and isoelectric focusing failed to resolve natriuretic activity from vasopressin and oxytocin. Similar results were observed following analysis of fractions isolated by gel filtration of acetic acid extracts of ventral hypothalamus tissue. The natriuretic fractions isolated from hypothalamic tissue were indistinguishable from oxytocin and vasopressin. These experiments suggest that the natriuretic activity in neurohypophyseal extracts can be attributed to oxytocin and vasopressin.
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PMID:Characterization of natriuretic activity from posterior pituitary lobes. 97 83

1. This study investigated the influences of calcium-channel blocking agents verapamil and diltiazem on platelet responses induced by arginine vasopressin (AVP) and lysine vasopressin (LVP). 2. The substances inhibited platelet aggregation induced by both low and high AVP concentrations, LVP and adrenaline plus AVP. IC50 values of each drug are lower than those determined for ADP- and collagen-elicited aggregation. Verapamil and diltiazem also decreased AVP-induced thromboxane B2 synthesis. 3. Other series of experiments showed that the addition of ethyleneglycol-bis-(beta-amino-ethyl ether) N, N'-tetra-acetic acid to platelet-rich plasma samples also prevented the platelet response to vasopressin polypeptides. 4. Our data provide evidence that the effects of verapamil and diltiazem on vasopressin-induced platelet responses may be directly related to inhibition of extracellular calcium entry.
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PMID:Calcium-channel blocking agents verapamil and diltiazem are inhibitors of vasopressin-induced human platelet activation. 178 23

Although the posterior pituitary is known to contain the PRL releasing activity or factor (PRF), its chemical identification has been a matter of dispute. In the present study, we purified PRF in porcine posterior pituitary extracts to chemically determine the primary structure. PRF activity was assessed during purification by the release of immunoreactive PRL from superfused rat pituitary cells. Two hundred seventy porcine posterior pituitaries were boiled, homogenized, and extracted with 2 M acetic acid. The acid extract was precipitated with 67% acetone, and the supernatant was absorbed onto a C18 column. The column was eluted step-wise with 10, 20, 30, 40, 50, and 60% acetonitrile (CH3CN) in 0.1% trifluoroacetic acid (TFA). The greatest PRF activity was recovered in the 30% CH3CN/0.1% TFA fraction and was further purified by ion-exchange chromatography on SP-Sephadex, followed by gel-filtration on Sephadex G-50. The Sephadex G-50 fractions with major PRF activity were finally purified by two cycles of reverse phase HPLC, yielding a single peak of PRF. Amino acid, as well as sequence analyses, indicated that the highly purified PRF was oxytocin. Authentic oxytocin showed the same chromatographic behavior and biological activity as those of the isolated peptide. In another experiment, desalted crude extracts of rat and porcine posterior pituitary tissues were directly chromatographed by reverse phase HPLC, and each fraction was assayed for PRF activity. Only two areas showed PRF activity; the largest activity coeluted with oxytocin and the smaller one co-eluted with vasopressin. The fractions which coeluted with oxytocin also showed oxytocin immunoreactivity, as examined by RIA. The results clearly indicated that the major PRF in these posterior pituitary extracts was oxytocin.
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PMID:Oxytocin is the major prolactin releasing factor in the posterior pituitary. 229 52

The 21 amino-acids endothelium-derived peptide, endothelin, recently isolated by Yanagisawa et al. (Nature 1988; 33, 411-5) possesses potent vasoconstrictive properties in vivo and in vitro. In the present study, we investigated the binding of endothelin on cultured rat aortic smooth muscle cells using 125I-iodotyrosyl-endothelin labelled by the chloramine T method. 125I-endothelin bound to a single class of hight affinity binding sites in vascular smooth muscle cells. After 2 hours incubation at 37 degrees C, dissociation constant (Kd) was 1.2 +/- 0.3 nM and binding capacity (Bmax) was 59 +/- 11 fmol/10(6) cells (n = 5). 125I-endothelin was displaced by unlabelled endothelin with a inhibition constant (Ki) of 0.2 nM, whereas an absence of competition was observed with 1 microM of vasoactive substances such as angiotensin II, arg-vasopressin, atrial natriuretic factor, histamine, epinephrine and norepinephrine, and with the calcium entry blocks nifedipine, diltiazem and D 600. 125I-endothelin binding was not reversible by addition of unlabelled endothelin (1 microM) and not dissociable by acetic acid (10 mM) or trypsin (0.1 p. 100) treatment of the cells. Furthermore, preincubation of vascular smooth muscle cells with endothelin (1 nM) at 37 degrees C induced a rapid down-regulation of endothelin binding capacity by about 50 p. 100. These data indicate that specific endothelin bindind sites are present in smooth muscle cells, and suggest a tight binding or a rapid captation of endothelin into the cell membrane leading to contractile events.
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PMID:[Presence of a specific binding site of endothelin on cultured smooth muscle cells]. 251 Jun 58


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