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)

Madin-Darby canine kidney (MDCK) cells grown in tissue culture have the morphological properties of distal tubular epithelial cells, form tight junctions, and lack several proximal tubular enzyme markers. Adenylate cyclase in these cells was stimulated by vasopressin, oxytocin, prostaglandins E1 and E2, glucagon, and cholera toxin. Hormone-stimulated adenylate cyclase activity in isolated membrane preparations was dependent on low concentrations of GTP and had the MgCl2 and pH optima expected for the kidney enzyme. The results, as well as the demonstration of enhanced hemicyst formation induced by cyclic AMP, suggest that the MDCK cell line has retained the differentiated properties of the kidney epithelial cell of origin. When MDCK cells were injected into baby nude mice, continuous nodule growth was observed until adulthood was attained. Histological studies revealed the presence of two cell types: normal mouse fibroblasts which comprise 80--90% of the solid nodule mass, and MDCK cells, which formed epithelial sheets lining internal fluid-filled glands. Electron microscope analysis showed that the mucosal surfaces of the cells were characterized by microvilli which faced the lumen of the glands, that adjacent MDCK cells were joined by tight junctions, and that the serosal surfaces of the epithelial sheets were characterized by smooth plasma membranes which were lined by a continuous basement membrane. These observations lead to the conclusion that the MDCK cells retain regional differentiation of their plasma membranes and the ability to regenerate kidney tubule-like structures in vivo.
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PMID:Retention of differentiated properties in an established dog kidney epithelial cell line (MDCK). 22 73

Cochleas from guinea pigs were perfused by isotonic buffer after punction of the carotid artery. The cochlea tissue was removed from the bony capsule and separated from the mediolus as band with a sharp needle under the microscope. Cell membranes were prepared subsequently from whole tissue. Purified membranes from the inner ear of guinea pigs contain adenylate cyclase which functionally is coupled with membrane receptors for vasopressin and beta-receptors for isoproterenol (epinephrine), respectively. Both hormones stimulate production of cyclic AMP at 37 degrees C. Furthermore, cyclase activity is increased by addition of Gpp (NH)p, a GTP analog. Possible relationships of these molecular events to cochlear events such as glycogenolysis, ionfluxes, transport and secretion mechanisms, and synaptic transmissions are discussed.
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PMID:Vasopressin and isoproterenol activate adenylate cyclase in the guinea pig inner ear. 22 50

In SLO-permeabilized isolated nerve endings from the rat neurohypophysis, GTP, guanosine 5'[y-thio]triphosphate (GTPyS) and guanosine 5'(beta y-imido]triphosphate (GMPPNP) inhibit the Ca(2+)-evoked vasopressin release. Pretreatment with pertussis toxin enhances the inhibitory effects of both GTP-analogues. Omission of Mg2+ overcomes the effect of GMPPNP and reverses the inhibitory effect of GTP and GTPyS. In the absence of Mg2+, GTP and GTPyS now potentiate Ca(2+)-evoked secretion.
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PMID:G-proteins mediate inhibition and activation of Ca(2+)-induced exocytosis from SLO-permeabilized peptidergic nerve endings. 129 36

Specific binding sites for the radio-iodinated oxytocin (OT) antagonist d(CH2)5-[Tyr(Me)2,Thr4, Tyr-NH2(9)]OVT ([125I]OTA) have been characterized on cultured hypothalamic astroglial cell membranes. The rate of association of the ligand to OT-binding sites was identical in the presence and the absence of the non-hydrolysable GTP analogue guanosine 5'-[beta gamma-imido]triphosphate (Gpp[NH]p, 0.1 mM), whereas the monophasic dissociation reaction became biphasic in the presence of Gpp[NH]p. Scatchard analysis of equilibrium binding of [125I]OTA resulted in a linear plot with a single class of binding sites (Kd 0.06 nM) which were insensitive to the addition of Gpp[NH]p. Unlabelled OT and [Arg8]vasopressin (AVP) bound to high- (H) and low- (L) affinity states with a dissociation constant ratio (KL/KH) of 100 for both hormones. Binding with both high and low affinity required the presence of Mg2+ in the incubation buffer, and the addition of Gpp[NH]p decreased the KL/KH ratio to 10 and increased the percentage of low-affinity binding sites. On the other hand, neither omission of Mg2+ from the buffer nor the addition of Gpp[NH]p altered the binding of either OT or V1 AVP antagonists to OT receptors. In the presence of a G-protein inactivator (N-ethylmaleimide; 3 mM) during OT competition studies the affinities of the two OT-binding sites were unchanged, but 90% of the high-affinity binding sites were converted into the low-affinity state. These results obtained with cultured hypothalamic astroglial cells provide further evidence for a coupling of OT receptors with a guanine-nucleotide-binding protein, with a requirement for Mg2+.
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PMID:Oxytocin receptors on cultured astroglial cells. Regulation by a guanine-nucleotide-binding protein and effect of Mg2+. 131 32

In deoxycorticosterone acetate (DOCA)-NaCl hypertension, the effects of vasopressin (VP) in the cortical collecting tubule (CCT) are exaggerated. These include both the biochemical effect of VP-stimulated adenosine 3',5'-cyclic monophosphate (cAMP) formation in the CCT and physiological effects of VP-mediated sodium and water retention. In this study, we examined the mechanism of enhanced VP-stimulated cAMP formation in the CCT. We compared cAMP formation in response to activators (following in parentheses) of the VP receptor (VP), of the stimulatory guanine nucleotide binding (Gs) protein [guanosine 5'-O-(3-thiotriphosphate) (GTP gamma S); F-], and of the catalytic subunit of adenylyl cyclase (forskolin, Mn2+) between control and DOCA-NaCl-treated rats. The effects of VP and forskolin were enhanced in CCT of DOCA-NaCl-treated animals by 201 and 139%, respectively, compared with control animals. Other activators, Mn2+ (150%), F- (142%), and GTP gamma S (156%), also caused augmented cAMP formation in the CCT of DOCA-NaCl-treated rats. The DOCA-NaCl-induced increment in cAMP response to VP remained after pretreatment of the rats with pertussis toxin (171 and 169% increase in response in DOCA-NaCl and control rats, respectively), suggesting that altered inhibitory guanine nucleotide binding (Gi) protein function is not the mechanism for the altered response to VP in the CCT. Further evidence that Gi function is intact in DOCA-NaCl animals is that epinephrine (via alpha 2-adrenoceptor stimulation) inhibited VP-stimulated cAMP accumulation to a similar degree in DOCA-NaCl and control rats (86 and 76%, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:DOCA-enhanced sites of vasopressin-stimulated cAMP formation in rat cortical collecting tubule. 133 10

Congenital nephrogenic diabetes insipidus (NDI) is an X-linked inherited disorder characterized by renal resistance to the antidiuretic hormonal action of vasopressin. This study describes the molecular basis of nephrogenic diabetes insipidus in a dog family. Kidney membranes prepared from NDI-affected male huskies were examined for vasopressin binding and response. Compared to membranes from unaffected canines, those from the kidney inner medulla of NDI-dogs possessed normal V2-receptor numbers, but with 10-fold lower affinity for [Arg8] vasopressin (AVP). Adenylate cyclase stimulation by AVP in contrast to that by forskolin or GTP-analogues was similarly reduced in a dose responsive manner. The NDI-affected dogs showed antidiuretic responses to very high doses of V2-specific agonists, consistent with their possessing V2-receptors of lower affinity. Prolonged treatment with V2-agonists, 1-deamino [D-Arg8] VP (dDAVP) and 1-deamino [Val4, Sar7] AVP (dVSAVP), rendered the NDI-affected dogs near normal in terms of water intake and urine osmolality.
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PMID:A low affinity vasopressin V2-receptor in inherited nephrogenic diabetes insipidus. 138 65

Adenylate cyclase activity was measured on membrane fractions from the gill epithelium of rainbow trout Salmo gairdneri. Basal and glucagon-stimulated activities responded negatively to homologous neurohypophyseal peptides (arginine-vasotocin and isotocin). This inhibitory effect was totally abolished in the presence of pertussis toxin (IAP). The guanine nucleotide dependence of the enzyme was further explored by using GTP, GDP, and their stable analogs Gpp(NH)p, GTP gamma S, and GDP beta S. The results suggest that neurohypophyseal peptides at low concentrations inhibit the adenylate cyclase system directly by way of a Gi-protein, thus implying the intervention of a new type of membrane receptor for these hormones in fish gills.
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PMID:Gi protein mediates adenylate cyclase inhibition by neurohypophyseal hormones in fish gill. 148 May 12

The binding of [3H]vasopressin (AVP) and the 125I-labelled vasopressin antagonist (VP-AT) d(CH2)5[Tyr2(Me),Tyr9(NH2)]AVP to rat liver membranes was examined with or without the addition of milimolar concentrations of divalent cations. The binding of vasopressin was enhanced by Mg2+ and Co2+ and markedly decreased by EGTA. The addition of EGTA and Mg2+ together restored the binding to a value similar to that of Mg2+ alone. On the contrary, the addition of Mg2+, Co2+, EGTA, and the combination of EGTA and Mg2+ decreased the binding of VP-AT to rat liver membranes. Kinetic analyses showed that Mg2+ increased the Kd twofold for VP-AT; that is from 0.13 nM to 0.28 nM. Moreover, it showed that the receptor with or without the addition of Mg2+ consists of a single population of binding sites, indicating that the receptor is switched from a high affinity to a low affinity state for VP-AT in the presence of 10 mM Mg2+. GTP gamma S was unable to block the effect of Mg2+ on the binding of VP-AT. These results suggest that this divalent cation interacts with receptor itself producing a conformational changes which thus modulates the affinity of the receptor.
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PMID:Modulation of the affinity of the vasopressin receptor by magnesium ions. 153 96

Two proteins have been identified in rat liver plasma membranes that bind a photoreactive GTP analogue, [32P]gamma-azidoanilido GTP, in response to incubation with the Ca(2+)-mobilizing agonist, vasopressin. The labeled proteins possess apparent molecular masses of 42 and 43 kDa. Their labeling requires Mg2+ and can be inhibited by GTP, its analogues, and GDP but not by other nucleotides. Vasopressin-stimulated labeling is attenuated by a V1 receptor-selective antagonist. The concentration of vasopressin required to stimulate labeling is in the same range (EC50 = 4 nM) as that required for activation of GTPase and phosphoinositide-specific phospholipase C activities in liver plasma membranes. Immunodetection and immunoprecipitation of the [32P]gamma-azidoanilido GTP-labeled 42- and 43-kDa proteins with antisera raised against peptide sequences in alpha q indicate that these proteins are members of the recently described Gq class of G proteins.
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PMID:Photoaffinity labeling of two rat liver plasma membrane proteins with [32P]gamma-azidoanilido GTP in response to vasopressin. Immunologic identification as alpha subunits of the Gq class of G proteins. 164 3

The mitogenic neuropeptides bombesin and vasopressin markedly increased tyrosine and serine phosphorylation of multiple substrates in quiescent Swiss 3T3 fibroblasts, including two major bands of Mr 90,000 and 115,000. Tyrosine phosphorylation of these proteins was increased as judged by immunoprecipitation of 32Pi-labeled cells and immunoblotting of unlabeled cells with monoclonal antiphosphotyrosine antibodies, elution with phenyl phosphate, and phospho amino acid analysis. Phosphotyrosyl proteins generated by bombesin and vasopressin did not correspond either by apparent molecular weight or by immunological and biochemical criteria to several known tyrosine kinase substrates, including phospholipase C gamma, the microtubule-associated protein 2 kinase, GTPase-activating protein, or phosphatidylinositol kinase. The effect was rapid (within seconds), concentration dependent, and inhibited by specific receptor antagonists for both bombesin and vasopressin. The endothelin-related peptide, vasoactive intestinal contractor, also elicited a rapid and concentration-dependent tyrosine/serine phosphorylation of a similar set of substrates. These results demonstrate that neuropeptides, acting through receptors linked to GTP-binding proteins, stimulate tyrosine phosphorylation of a common set of substrates in quiescent Swiss 3T3 cells and suggest the existence of an additional signal transduction pathway in neuropeptide-induced mitogenesis.
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PMID:Bombesin, vasopressin, and endothelin rapidly stimulate tyrosine phosphorylation in intact Swiss 3T3 cells. 164 10


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