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)

Tumour-promoting phorbol esters (phorbol-12-myristate-13-acetate, PMA; phorbol-12,13-dibutyrate, PDBu) but not 4 beta-phorbol, activate protein kinase C. Using human platelets pre-labelled with quin2 or 32PO4 we examined the effects of these compounds on human platelet cytosolic free Ca2+ ([Ca2+]i) and on [32P]phosphatidic acid ([32P]PtdOH). PMA and PDBu, but not 4 beta-phorbol inhibited thrombin-, PAF- and vasopressin-induced elevation of [Ca2+]i and [32P]PtdOH formation. It is suggested that protein kinase C may act to terminate the transduction processes that link receptor occupancy to cellular activation.
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PMID:Tumour-promoting phorbol esters inhibit agonist-induced phosphatidate formation and Ca2+ flux in human platelets. 298 15

An assay procedure for carnitine palmitoyltransferase is described which allows rapid measurement of the overt activity of this enzyme in isolated rat hepatocytes. In a one-step procedure digitonin permeabilizes the plasma membrane and at the same time carnitine palmitoyltransferase activity is measured. The use of the present procedure shows that carnitine palmitoyltransferase activity is regulated on the short term by different types of agonists. Thus, insulin, epidermal growth factor, vasopressin and the phorbol ester PMA inhibit carnitine palmitoyltransferase activity, whereas glucagon treatment renders the enzyme more active. These changes in enzyme activity coincide with corresponding changes in the rate of fatty acid oxidation.
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PMID:Short-term regulation of carnitine palmitoyltransferase activity in isolated rat hepatocytes. 334 11

Arginine vasopressin stimulated the accumulation of labeled inositol phosphate in cultured rat aortic myocytes prelabeled with tritiated myo-inositol. This accumulation was prevented by pretreating the myocytes with the phorbol ester PMA. The time-course and concentration-effect curves were similar for inositol phosphate formation in myocytes and contractile effects on isolated aorta. Vasopressin agonists also stimulated inositol phosphate formation, whereas vasopressin-induced response could be inhibited by V1a-specific antagonists. These results suggest that stimulation of inositol phosphate formation in myocytes is due to V1a receptor activation and could be modulated by protein-kinase-C-mediated mechanisms.
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PMID:V1a vasopressin-induced accumulation of inositol trisphosphate in cultured rat aortic myocytes; modulation by protein kinase C. 349 Aug 52

Polyclonal antibodies were raised to isolated toad bladder granules. On immunoblots, the anti-granule antiserum specifically stained components of isolated granules. Immunocytochemically, the anti-granule antiserum labeled the apical surface of the bladder. Immunolabeling increased at the apical surface when the bladder was exposed to antidiuretic hormone (ADH) serosally or phorbol ester (PMA) mucosally--conditions which stimulate apical granule exocytosis. The increase in granule epitopes on the apical surface was sixfold greater than the net increase in surface area.
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PMID:ADH and phorbol ester increase immunolabeling of the toad bladder apical membrane by antibodies made to granules. 361 64

A chemical method has been established for the detection of carboxyl-terminally amidated peptides in tissue extracts. Tissue was homogenized in an acidic medium designed to solubilize peptides while precipitating high-molecular-weight protein. The homogenate supernatant was in turn subjected to reversed-phase extraction with C18 Sep-Pak cartridges. The eluates were fractionated by reversed-phase high-performance liquid chromatography (RP-HPLC). Individual fractions were exhaustively digested with thermolysin, derivatized with phenylisothiocyanate (PITC), and then subjected to ethyl acetate extraction under basic conditions. The phenylthiocarbamyl (PTC)-amino acid amide derivatives were selectively taken up into the organic phase, while the other digestion products remained in the aqueous phase. The organic phase was analyzed by RP-HPLC on a Pico-Tag amino acid analysis column, monitoring eluates at 254 nm. PTC-amino acid amides were identified and quantitated by comparing their elution positions and peak areas, respectively, with those of standards. Their identities were confirmed by amino acid analysis, following hydrolysis with hydriodic acid. The technique was applied to extracts of bovine posterior pituitaries and a human medullary thyroid carcinoma. Vasopressin (-Leu-Gly-amide), oxytocin (-Gly-amide), Lys1 gamma 1-melanotropin (-Phe-amide), and various acetylated and non-acetylated forms of alpha-melanotropin (-Val-amide) were identified in the posterior pituitary extract. Various forms of calcitonin (-Val-Gly-Ala-Pro-amide) were detected in the tumour extract. For vasopressin and calcitonin the thermolytic digest resulted in di- and tetra-peptides, respectively, reflecting thermolytic cleavage at more favoured sites.
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PMID:Use of Pico-Tag methodology in the chemical analysis of peptides with carboxyl-terminal amides. 373 29

The induction of the hydroosmotic response in the toad urinary bladder is considered to be associated with membrane addition mediated by exocytosis at the affected luminal membrane and reversed by endocytic retrieval at that surface. The permeability, exocytosis and endocytosis are initiated by antidiuretic hormone (ADH) receptor interaction on the basolateral membrane. In other hormone responsive systems, phorbol ester (phorbol myristate acetate, PMA), a tumor promoter, has been implicated in the regulation of various transport processes through the activation of protein kinase C and cytoskeletal protein phosphorylation. We found that addition of 10(-6) M PMA to the mucosa induces an hydroosmotic response which is gradual and which reaches a maximum within 60 min, equal to about 1/3 the maximal ADH response. Morphologically, PMA causes rapid exocytosis of the granules, endocytosis of horseradish peroxidase from the mucosal medium into tubules and multivesicular bodies and elongation of apical microvilli. Controls treated with mucosal 0.1% dimethylsulfoxide (DMSO) or an inactive PMA isomer on the mucosal surface, or PMA on the serosal surface lack the hydroosmotic, exocytic, endocytic and cytoskeletal changes. Addition of serosal ADH to PMA-treated bladders results in a precocious hydroosmotic and exocytic ADH response, but a lowering of the maximal response. Also pretreatment of bladders with PMA prevented the ADH-induced increase in transepithelial potential difference. Thus, apical events mediating the PMA hydroosmotic response are correlated with exo- and endocytosis and elongation of apical microvilli.
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PMID:Phorbol myristate acetate induces endocytosis as well as exocytosis and hydroosmosis in toad urinary bladder. 393 62

The effect of experimental poisoning by organic compounds, frequently used in agriculture as fungicides, on the histochemical and histoenzymic pattern of the hypothalamic neurosecretory system has been studied. The experimental rats were fed by means of a gastric tube with the following compounds: Phenylmercuryacetate, 0.1 g daily, for 10 days; Aethylmercury-p-toluenesulphanilide, 0.2 g daily, for 10 days, and Methoxyethylmercurychloride (Ceresan), 0.1 g daily, for 6 days. The histochemical and histoenzymic investigations have shown that ingestion of Phenylmercuryacetate brought about an increase in the release of antidiuretic hormone (ADH) with a concomitant enhancement of production of neurosecretory substances. The peroral administration of Aethylmercury-p-toluenesulphanilide and of Methoxyethylmercury chloride instead, resulted in the accumulation of the neurosecretion within the hypothalamic-hypophyseal system with a parallel inhibition of ADH release. The experimental poisoning of Ceresan had also a stimulatory effect on the activity of many enzymes in the neurosecretory nuclei of the rat hypothalamus. Morphological changes resulting from the experimental intoxication were only rarely observed in the neurosecretory cells of the investigated hypothalamic nuclei.
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PMID:[Histochemical changes in the neurosecretory hypothalamic nuclei as result of an intoxication with mercury compounds (author's transl)]. 626 74

Hormonal activation of protein kinase C (PKC) is a major signaling mechanism regulating salt and water transport in the distal nephron. We used antisense DNA to down-regulate a PKC isoform in the rabbit cortical collecting duct (CCD) and examined its role in mediating arginine vasopressin's (AVP) effect on salt transport in the CCD. Immunoblots demonstrate that PKC-epsilon (diacylglycerol sensitive) and PKC-zeta (diacylglycerol insensitive) are the major PKC isoforms in both freshly isolated and primary cultures of rabbit CCDs. Rabbit CCDs grown on semi-permeable supports, displayed a positive baseline short circuit current (Isc), which was abolished by amiloride, demonstrating active Na+ absorption. Both AVP and 8-chloro-phenylthio-cAMP (8CPTcAMP) transiently increased Isc, however, within 40 min Isc fell below baseline. Down-regulation of PKC-epsilon, as confirmed by immunoblot, was achieved either by treatment with a PKC-epsilon-specific antisense oligonucleotide or 48 h of 1 microM PMA. In PKC-epsilon down-regulated cells, 8CPTcAMP produced a sustained, rather than transient, increase in Isc. We suggest cAMP stimulates Na+ transport, but secondary activation of PKC-epsilon results in the sustained inhibition of Na+ transport seen in response to vasopressin in the CCD.
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PMID:Anti sense DNA down-regulates proteins kinase C-epsilon and enhances vasopressin-stimulated Na+ absorption in rabbit cortical collecting duct. 776 15

Angiotensin II (AII)- and Arg8-vasopressin (AVP)-regulated gene expression in vascular cells has been reported to contribute to vascular homeostasis and hypertrophy. In this report, AVP-induced expression of plasminogen activator inhibitor (PAI)-2 mRNA in rat microvessel endothelial (RME) cells was identified using differential mRNA display. Further characterization of vasoactive peptide effects on PAI expression revealed that AII stimulated a 44.8 +/- 25.2-fold and a 12.4 +/- 3.2-fold increase in PAI-2 mRNA in RME cells and rat aortic smooth muscle cells (RASMC), respectively. AII also stimulated a 10- and 48-fold increase in PAI-1 mRNA in RME cells and RASMC, respectively. These AII effects were inhibited by either Sar1, Ile8-angiotensin or the AT1 antagonist DuP 735, but were not significantly altered in the presence of the AT2 antagonist PD123319. AII stimulation of RASMC and RME cells also significantly increased both PAI-1 protein and PAI activity released to the culture medium. Inhibition of protein kinase C completely blocked PMA-stimulated induction of PAI-2 mRNA in both cell types and inhibited the AII-stimulated increase in RASMC by 98.6 +/- 2.8%. In contrast, protein kinase C inhibition only partially decreased the AII-stimulated PAI-2 expression in RME cells by 68.8 +/- 11.1%, suggesting that a protein kinase C-independent mechanism contributes to a 6.9 +/- 1.5-fold AII induction of PAI-2 expression in endothelial cells. AII and PMA also stimulated protein tyrosine phosphorylation in RME cells, and the tyrosine kinase inhibitor genistein partially blocked their induction of PAI-2 mRNA. These findings suggest that AII may regulate plasminogen activation in the vasculature by inducing both PAI-1 and PAI-2 expression.
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PMID:Angiotensin II induces plasminogen activator inhibitor-1 and -2 expression in vascular endothelial and smooth muscle cells. 788 82

Arginine vasopressin mediates its effects through vasopressin receptor activation and second messenger production. Recent cloning of the V1a receptor provided the opportunity to investigate the possible signal transduction pathways associated with this single vasopressin receptor subtype. When stably expressed in CHO cells, vasopressin stimulated several signal transduction pathways simultaneously including calcium influx, phospholipase A2, phospholipase C, and phospholipase D. Vasopressin-stimulated release of arachidonic acid, IP3 formation, and phosphatidylethanol formation (in the presence of 1% ethanol) were used as indexes of phospholipase A2, phospholipase C, and phospholipase D activation, respectively. V1a receptor-activation stimulated a peak followed by a sustained plateau phase of intracellular calcium. The plateau phase was dependent on extracellular calcium, insensitive to blockers of voltage sensitive calcium channels, blocked by heavy metals, and quenched when MnCl2 was present in the extracellular media. Removal of extracellular calcium blunted the release of IP3, and blocked the release of arachidonic acid and phosphatidylethanol indicating that these responses were at least in part regulated by receptor-operated calcium influx. Vasopressin-stimulated release of arachidonic acid and phosphatidylethanol were augmented with the phorbol ester PMA, and this augmentation was blocked by inhibitors of protein kinase C and absent with long-term PMA treatment. Vasopressin-stimulated IP3 release was inhibited with PMA and the inhibition reversed with protein kinase C inhibitors.
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PMID:The cloned vasopressin V1a receptor stimulates phospholipase A2, phospholipase C, and phospholipase D through activation of receptor-operated calcium channels. 796 20


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