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)

The two types of neurophysins known in vertebrate species, namely MSEL-neurophysin (vasopressin-like hormone-associated neurophysin) and VLDV-neurophysin (oxytocin-like hormone-associated neurophysin) have been purified from the pollack (Pollachius virens) pituitary through a combination of molecular sieving and high-pressure liquid chromatography (HPLC). Homogeneity has been checked by gel electrophoresis and return in HPLC. The apparent molecular masses measured by SDS-electrophoresis are near 12 kDa, significantly higher than those found for their mammalian homologues (10 kDa). The two types of neurophysins have been recognized through their N-terminal amino acid sequences. The primary structure of MSEL-neurophysin has been partially determined using automated Edman degradation applied on native and reduced-alkylated protein, as well as peptides derived by trypsin or staphylococcal proteinase hydrolyses. Comparison of pollack MSEL-neurophysin with ox, goose and frog counterparts reveals that particular positions in the polypeptide chain are subjected to substitutions and that the numbers of substitutions do not seem closely related to the paleontological times of divergence between the different vertebrate classes.
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PMID:Bony fish neurophysins. Identification of MSEL- and VLDV-neurophysins of the pollack (Pollachius virens). 798 56

The norepinephrine (NE) content in discrete brain areas and the vasopressin content in the neurohypophysial system were assessed in rats after a 9-d spaceflight and after a recovery period (9 d). The NE content in the locus coeruleus decreased significantly in spaceflight rats (2.9 +/- 0.3 vs. 8.9 +/- 0.7 pmol.structure-1 for control rats, p < 0.001), but showed no difference between control and flight animals after a 9-d recovery. These findings were probably due to an acute stress undergone during landing. The NE content was unchanged in the A2 and A5 cell groups. In rats flown aboard SLS-1, the vasopressin content was increased in the posterior pituitary (1.47 +/- 0.1 vs. 0.86 +/- 0.1 micrograms.structure-1, for control rats, p < 0.01), and was significantly decreased in the hypothalamus (8.95 +/- 2.0 vs. 17.6 +/- 2.2 ng.structure-1, for control rats, p < 0.05). We conclude that the NE depletion in the locus coeruleus and the alteration in vasopressin release were consistent with an acute stress, likely occurring during and/or after landing. These changes tend to mask the actual neuroendocrine modifications caused by microgravity.
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PMID:Norepinephrine content in discrete brain areas and neurohypophysial vasopressin in rats after a 9-d spaceflight (SLS-1). 833 96

Production by small-cell carcinoma (SCCL) of neurophysins (HNPs) and neurophysin-related cell-surface antigen (NRSA) was examined for two cell lines, for mouse xenografts, and for a resected human tumor, using polyclonal and monoclonal antibodies to vasopressin-associated human neurophysin (VP-HNP) and polyclonal antibodies to vasopressin (VP). The nature of the mRNA responsible for giving rise to these neurophysin-related products was investigated by performing Northern analysis on preparations of poly A+RNA and cDNA probes complimentary to portions of the exon A, exon B, and exon C regions of the human VP gene. SDS-electrophoresis and Western analysis revealed two prominent proteins of 42,000 and 20,000 Da in acid extracts from all SCCL sources when the monoclonal anti-HNP or one of the two polyclonal anti-HNP preparations were used. These antibodies also disclosed the presence of a minor component of 10,000 Da. A second polyclonal anti-HNP preparation reacted with one prominent protein of 30,000 Da and, for one cell line and mouse xenografts, another protein of 32,000 Da. Both of two anti-VP preparations reacted with proteins of 42,000, 30,000, 25,000, and 20,000 Da in extracts from all SCCL source material. The immunoreactive proteins of 42,000, 30,000, and 20,000 Da were all components of a membrane fraction from SCCL cells and tissues. In Northern analysis, a single RNA of about 900 bases hybridized with exon A and exon B probes, but not with the cDNA probe complimentary to exon C of the VP gene.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Vasopressin mRNA and neurophysin-related cell-surface antigen (NRSA) in small-cell carcinoma. 838 89

We have characterized a specific binding site for angiotensin IV on bovine aortic endothelial cell membranes. Pseudo-equilibrium studies at 37 degrees C for 2 h have shown that this binding site recognizes angiotensin IV with a high affinity (Kd = 0.71; average of two experiments that yielded values of 0.71 and 0.72 nM). The binding site is saturable and relatively abundant with a maximal binding capacity of 0.59 pmol/mg protein (average of two experiments that yielded values of 0.39 and 0.78 pmol/mg of protein). Non-equilibrium kinetic analyses at 37 degree C revealed a calculated Kd of 59 pM (average of two experiments that yielded values of 67 and 50 pM). The binding site displays a high affinity for angiotensin receptors AT1 or AT2. An analysis of specificity showed that the binding site displays a high affinity for angiotensin IV, low affinities for angiotensin II, [Sar1, Val5, Ala8]angiotensin II and does not recognize L-158,809 (5,7-dimethyl-2-ethyl-3-[(2'-(1 H-tetrazole-5-yl)[1,1'-biphenyl]-4-yl)methyl]-3H-imidazo[4, 5-beta]pyridine H2O) and PD 123319 (1-[4-dimethylamino)3-methylphenyl]methyl-5-(diphenylacetyl) 4,5,6,7-tetrahydro-1 H-imidazo[4,5-c]pyridine-6-carboxylic acid). A few unrelated hormones (bradykinin, [Arg8] vasopressin, endothelin-1, atrial natriuretic factor, isoproterenol and adrenocorticotropic hormone) were unable to inhibit any 125I-angiotensin IV binding. The affinities of different structural analogues of angiotensin IV revealed that the N-terminal position is critical for receptor recognition and the C-terminal proline is also important. GTP gamma S and polyvinyl sulfate did not affect the binding, suggesting that the receptor is not coupled to a G-protein. The divalent cations Mg2+ and Ca2+ were shown to diminish the binding of 125I-angiotensin IV. Cross-linking of 125I-angiotensin IV to bovine aortic endothelial cell membranes in the presence of disuccinimidyl suberate, followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) revealed a major band of 186 +/- 12 kDa. The presence in high concentration of this angiotensin binding site on aortic endothelial cells suggest the existence of a novel mechanism involved in the control of vascular tone or vascular permeability.
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PMID:Characterization of a binding site for angiotensin IV on bovine aortic endothelial cells. 856 70

We have previously established that the eleven cytosolic peptides phosphorylated in response to acute glucagon challenge in isolated rat hepatocytes undergo rapid dephosphorylation following transfer to medium free of 32PO4(3-). This dephosphorylation, far from being a simple process, is complex and asynchronous. This novel finding of asynchrony raises the question of whether, by analogy to glucagon, protein dephosphorylation is asynchronous during the recovery phase from acute challenge with noradrenaline, vasopressin or angiotensin II. One-dimensional SDS-PAGE of hepatocyte extracts indicates that noradrenaline stimulates the phosphorylation of ten cytosolic peptides, whereas vasopressin and angiotensin II stimulate the phosphorylation of six cytosolic peptides. Transfer of the hormone-challenged hepatocytes to medium devoid of 32PO4(3-) and hormone led to the rapid net dephosphorylation of the 32P-labelled phosphopeptides, albeit at different rates. In all instances, the most rapidly dephosphorylated phosphopeptide was glycogen phosphorylase. Statistical analysis indicates that during recovery from noradrenaline challenge three distinct groups of phosphopeptides can be delineated on the basis of their rates of dephosphorylation. Despite the fact that vasopressin and angiotensin II stimulate the phosphorylation of the same sub-set of phosphopeptides, there were differences in the rates of dephosphorylation of these phosphopeptides during the recovery phase from acute hormonal challenge.
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PMID:Recovery from acute challenge with noradrenaline, vasopressin and angiotensin II in isolated rat hepatocytes. 859 6

The potential roles of protein tyrosine kinases (TKs) and of phosphotyrosine phosphatases (PTPs) in pancreatic islet function are not known. In this study, we investigated whether vanadate, a potent PTP inhibitor, affects phosphoinositide (PI) metabolism by a TK-dependent pathway in isolated mouse islets. To avoid the confounding effects of changes in Ca2+ influx, all experiments were performed in the absence of Ca2+. In the presence of 15mM glucose, vanadate, acetylcholine (ACh) or [Arg]vasopressin (AVP) strongly stimulated InsP production. Vanadate also increased PtdInsP levels in membranes. The TK inhibitor genistein (not its inactive analogues genistin and daidzein) significantly reduced vanadate effects, but was without effect in the absence of stimulation or in the presence of ACh or AVP. Islet proteins resolved by SDS/PAGE were analysed by immunobloting with anti-phosphotyrosine antibody. Under control conditions, several phosphotyrosyl-proteins (PYPs) were present. Vanadate increased phosphotyrosine residues on several PYPs, notably two proteins of 145 and 85 kDa. This effect was prevented by genistein, p145 and p85 could correspond to phospholipate Cgamma(PLCgamma) and the regulatory subunit of PtdIns-3-kinase (PtdIns-3K) respectively. Both proteins are expressed in islets, as revealed by immunoblots with specific antibodies. Tungstate, another PTP inhibitor, reproduced vanadate effects, but inhibition of PtdIns-3K by wortmannin failed to affect vanadate-increased PtdInsP levels. Incubation of the islets in the presence of 10% (v/v) fetal calf serum instead of BSA increased InsP production and this effect was prevented by genistein. These results suggest that inhibition of PTP increases InsP production in mouse islets by a TK-dependent pathway. They also provide evidence for a potential role of TK and PTP in pancreatic B-cell function.
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PMID:Possible involvement of a tyrosine kinase-dependent pathway in the regulation of phosphoinositide metabolism by vanadate in normal mouse islets. 867 Jan 31

We report here a study of photoaffinity labeling of the V1a-vasopressin receptor with high-affinity, V1-specific radioiodinated antagonist ligands: one containing an azidophenylalanine residue ([beta,beta-dimethyl-beta-mercaptopropionyl(1), p-azido-Phe2,Val4,Lys8,D-Tyr9] vasopressin), two others containing nitrophenylalanine, and one, highly similar but without a photosensitive function, as control. All analogues competed in the dark for the same binding site with vasopressin. Long-wavelength UV irradiation of rat liver membranes incubated in presence of the radio-iodinated azido photolabel produced a specifically labeled protein band at 53 kDa in SDS-PAGE. Identical experiments with the nitrophenylalanyl peptides produced only non-specific labeling and control experiments with the non-photosensitive analogue produced no labeling at all. Chemical crosslinking of 3H-VP to the same membrane preparation produced a result identical to that of the azido photolabel, confirming the receptor nature of the labeled protein. Deglycosylation of the labeled receptor with endoglycosidase F reduced the observed molecular weight of 53 kDa to 43 kDa. The molecular parameters reported herein of the presumed hepatic vasopressin receptor confirm the values deduced from the molecular cloning of the rat V1a receptor.
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PMID:Molecular weight determination of the hepatic vasopressin receptor with a high-affinity photoprobe. 891 57

Transient and stable expression in eukaryotic cells is commonly used to examine receptor function. Characterization of the V2 vasopressin receptor synthesized in transiently transfected cells revealed the presence of large quantities of immature protein and a small fraction of fully mature protein. The immature protein was characterized by its sensitivity to endoglycosidase H treatment, abnormal migration in SDS PAGE, and a tendency to form aggregates. Prevention of protein glycosylation by mutagenesis increased the fraction of mature protein produced, but did not eliminate the need for the maturation step. On the other hand, stably transfected cells produce almost exclusively mature receptor protein with a t1/2 of 6 h, while the immature form has a t1/2 of 20 min. In the absence of N-linked glycosylation the t1/2 of the mature V2 receptor in stably transfected cells was reduced to 4.5 h. In transient expression experiments the immature receptor proteins exhibited a prolonged t1/2 of about 8 h. Comparison of the half life of the immature form of the wild type and the R137H mutant V2 receptor did not reveal differences despite the lower amounts of mutant mature receptor detected by binding.
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PMID:Maturation of receptor proteins in eukaryotic expression systems. 902 6

Function and biochemical properties of the V2 vasopressin receptor (V2R) mutant R337ter, identified in patients suffering from X-linked recessive nephrogenic diabetes insipidus, were investigated by expression in COS.M6 or HEK293 cells. Binding assays and measurements of adenylyl cyclase activity failed to detect function for the truncated receptor, although metabolic labeling demonstrated normal levels of protein synthesis. ELISA assays performed on cells expressing the receptors tagged at the amino terminus with the HA epitope failed to detect V2R R337ter on the plasma membrane. Treatment with endoglycosidase H revealed that the receptor was present only as a precursor form because the mature R337ter V2R, resistant to endoglycosidase H treatment, was not detected. The precursor of V2R-R337ter had a longer half-life than that of the wild type V2R, suggesting that arrested maturation may slow the degradation of the precursor. Unrelated experiments had demonstrated that V2R-G345ter, containing eight additional amino acids, was expressed on the plasma membrane and functioned normally. Receptor truncations longer than 337ter revealed that four of the eight amino acids identified initially provided the minimum length required for the protein to acquire cell surface expression. This was shown by the production of mature receptor (V2R-341ter) detectable in SDS-PAGE, which mediated arginine vasopressin stimulation of adenylyl cyclase activity and bound ligand. In addition, the identity of amino acid 340 was found to play a role in this phenomenon. In conclusion, these data demonstrate that the V2R R337ter is nonfunctional because it does not reach the plasma membrane and that the minimal protein length required for translocation of the V2R to the cell surface is sufficient to confer function to the receptor protein. They also suggest the existence of a protein quality control in the endoplasmic reticulum independent of glycosylation.
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PMID:An X-linked NDI mutation reveals a requirement for cell surface V2R expression. 917 Dec 34

We have synthesized and fully characterized by fast-atom-bombardment-mass, NMR and ultraviolet spectroscopies the vasopressin antagonist 3-azidophenylpropionyl-D-Tyr(Me)-Phe-Gln-Asn-Arg-Pro-Arg-Tyr(3I )-NH2. Easily radioiodinatable just before use, it has a high affinity for the natural rat liver V1a receptor [dissociation constant (Kd) = 54 +/- 20 pM; Carnazzi, E., Aumelas, A., Barberis, C., Guillon, G. & Seyer, R. (1994) J. Med. Chem. 37, 1841-1849] and for both the rat vasopressin V1a receptor expressed in Spodoptera frugiperda 9 cells (Sf9 cells, Kd = 688 +/- 35 pM) and in COS-7 cells (Kd = 320 +/- 20 pM). This probe labels specifically the V1a receptors in an ultraviolet-dependent manner, and binds covalently to about 12% of the receptors with high stability over several days, even in dissociation or solubilization conditions. SDS/PAGE studies and autoradiographic analyses of the photolabeled receptors reveal a single band (49.5 kDa) and two bands (63 kDa and 93.6 kDa) for receptor-probe associations obtained in Sf9 and COS-7 cells respectively. These molecular masses are consistent with non-glycosylated and highly glycosylated forms of the receptor, according to each expression system. In rat liver membranes, we have identified apparent molecular masses of about 32, 45 and more than 67 kDa. We finally demonstrated a proteolysis of the receptor that appeared to be Zn2+ and leupeptin sensitive. The high potency of this ligand is promising for the monitoring of the purification of the V1a receptor and for mapping its antagonist-binding site.
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PMID:Efficient photoaffinity labeling of the rat V1a vasopressin receptor using a linear azidopeptidic antagonist. 928 14


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