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)

In addition to oxytocin (OT), vasopressin (AVP) and their respective neurophysins (NPs), another [35S]cysteine incorporating component is present in the guinea pig neurohypophysis. Gel filtration and Con A affinity chromatography revealed that this component was larger than NP and was glycosylated. NP-immunoreactivity was assessed using antisera which distinguish the OT- and AVP-related NPs. Whilst the anti-NP antiserum detected only one component (guinea pig NP), the anti-NP antiserum detected both NP and the glycosylated 35S-labelled component. These results suggest that a significant amount of NP in guinea pig neural lobes bears a glycopeptide extension and represents a partially processed form of the AVP precursor in this species.
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PMID:Characterisation of an intermediate in neurophysin biosynthesis in the guinea pig. 664 47

We have developed small-scale methods for the isolation and biochemical characterization of subcellular fractions from single guinea-pig posterior-pituitary glands. Secretory vesicles and coated microvesicles produced in this way were of similar purity to those isolated from large amounts of tissue by conventional ultracentrifugation. [35S]Cysteine injected into the hypothalamus was found in the soluble contents of secretory vesicles isolated from the neural lobes 24 h later. High-pressure liquid-chromatographic analysis revealed that the radiolabel was incorporated into the expected neurosecretory products (oxytocin, vasopressin and neurophysin) and also into a biosynthetic intermediate in the vasopressin system. The membranes of secretory vesicles were labelled with [3H]choline 24 h after its hypothalamic injection. Little or no [3H]choline could be demonstrated in coated microvesicles at this time, although these structures were labelled 5 days after injection. Stimulating hormone secretion by chronic dehydration produced a significant fall in [3H]choline content of the secretory-vesicle membranes without any transfer of label into coated microvesicles, suggesting that coated microvesicles are not involved in membrane retrieval in the neurohypophysis.
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PMID:Membrane retrieval in the guinea-pig neurohypophysis. Isolation and characterization of secretory vesicles and coated microvesicles after radiolabel incorporation in vivo. 671 33

Carboxamidopeptidase, an enzyme which inactivates neurohypophyseal hormones, has been purified 3800-fold in an overall yield of 22% from toad skin, a neurohypophyseal hormone target organ, by (NH4)2SO4 fractionation, DEAE-Sephadex chromatography, and affinity chromatography on immobilized p-aminobenzamidine and concanavalin A-agrose. The purified enzyme is capable of inactivating both [8-arginine]vasopressin (AVP) and oxytocin by hydrolyzing the Arg8-Gly9-NH2 and the Leu8-Gly9-NH2 bonds, respectively, and can hydrolyze the ester substrates, benzoyl-L-arginine ethyl ester (BzArgOEt) and acetyl-L-trypsine ethyl ester, suggesting that the enzyme has both trypsin-like and chymotrypsin-like activities. Carboxamidopeptidase is maximally active at pH 7.5-8.5 for AVP and BzArgOEt and pH 7.0 for oxytocin. Carboxamidopeptidase is inhibited by ovoinhibitor, ovomucoid, Trasylol. lima bean trypsin inhibitor, concanavalin A, antipain, leupeptin, chymostatin, elastatinal, p-nitrophenyl p-guanidinobenzoate, and 4-methylumbelliferyl p-guanidinobenzoate but not by soybean trypsin inhibitor, alpha 1-antitrypsin, hirudin, pepstatin, bestatin, phosphoramidon, or cysteine. The enzyme is also inhibited by the serine protease inhibitor, diisopropyl phosphofluoridate (i-Pr2PF), and by the chloromethyl ketone derivatives of tosyllysine, tosylphenylalanine, and (benzyloxycarbonyl)phenylalanine, as well as by the sulfhydryl group reagent, p-(chloromercuri)benzoate (PCMB). Inhibition by PCMB is reversed by cysteine. The molecular weight determined by gel filtration in the presence of 1 MNaCl is approximately 100 000. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicates that the enzyme is composed of two identical subunits of 48 000 daltons. Each subunit consists of a heavy chain (28 000 daltons) and a light chain (19 000 daltons) joined by a disulfide bond(s). Labeling experiments using [3H]-i-Pr2PF showed that the enzyme active site is located in the heavy chain.
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PMID:Carboxamidopeptidase: purification and characterization of a neurohypophyseal hormone inactivating peptidase from toad skin. 676 14

We synthesized a series of analogs of arginine vasotocin by systematically substituting each residue, and we then evaluated the anovulatory activity of these compounds in the rat, investigating the correlation between molecular structure and anovulatory, pressor, and antidiuretic activities. Substitution of the N-terminus cysteine with 3-mercaptopropanoic acid in arginine vasotocin and arginine vasopressin produced a 3- to 4-fold increase in both anovulatory and antidiuretic activity and only a 10% change in pressor activity. A similar substitution with lysine vasopressin produced no significant change in either anovulatory or antidiuretic potency; however, the pressor activity was reduced by half. Substitution of this cysteine in arginine vasotocin with 2-hydroxy-3-mercaptopropanoic acid produced an analog more potent in anovulatory activity than arginine vasotocin but less potent than [1-(3-mercaptopropanoic acid)]-arginine vasotocin. The most potent anovulatory analog synthesized was [1-(3-mercaptopropanoic acid)]-8-ornithine vasotocin, which gave a 10-fold increase in anovulatory activity, a 4-fold reduction in antidiuretic activity, and only a 10% increase in pressor potency when compared with arginine vasotocin. These data suggest that different receptors are involved in the anovulatory and antidiuretic responses, but that the anovulatory and pressor effects may be mediated through similar receptors. Further work is necessary to produce a peptide that possesses specific anovulatory activity.
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PMID:Anovulatory effect of synthetic analogs of arginine vasotocin in the rat. 684 22

The 3-nitro-2-pyridinesulfenyl (Npys) group has been used successfully for side chain protection of cysteine during the stepwise solid-phase synthesis of Lys8-vasopressin (LVP) on benzhydrylamine resin. The versatility and limitations of this group have been evaluated by comparison of this synthesis with a parallel control synthesis using the 3,4-dimethylbenzyl (DMB) group and with a synthesis utilizing a combination of both groups. The Npys group was found to be stable to TFA as reported and, in addition, was found to be stable to HF: anisole (9:1) for 45 min at 0 degree, but not when thiol was present in either reagent. Furthermore, compatibility of the Npys group with the Boc-benzyl synthetic tactic in solid-phase peptide synthesis was demonstrated. LVP with full biological activity was obtained after purification by gel filtration and reverse-phase HPLC.
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PMID:Sulfur protection with the 3-nitro-2-pyridine sulfenyl group in solid-phase peptide synthesis. 711 19

A reverse-phase high performance liquid-chromatography (h.p.l.c.) protocol has been developed, whereby all the major known posterior-pituitary components that are derived from the processing of pro-oxytocin and pro-vasopressin can be separated one from another. Thus, in a single chromatographic step, it has been possible to separate vasopressin (VP), oxytocin (OT), oxytocin-neurophysin (rOT-Np), vasopressin-neurophysin (rVP-Np) and vasopressin-glycopeptide (rVP-GP) from acid extracts of the neurointermediate lobes of rat pituitary glands. All these peptides except rVP-GP were labelled in the neural lobe by 24h after a hypothalamic injection of [35S]cysteine, whereas all except VP were labelled by 24h after a similar injection of [3H]leucine. Three major labelled proteins were isolated from 20 min [35S]cysteine-injected rats when extracts of the supraoptic nucleus were subjected to Sephadex G-75 chromatography, h.p.l.c. and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. Immunoprecipitation with antisera raised against rat neurophysins, VP and OT revealed 21000- and 19000-mol.wt. common precursors to VP and rVP-Np and a 15000-mol.wt. common precursor to OT and rOT-Np. Some immunoreactive rVP-Np could occasionally be detected in the Vo of Sephadex G-75 chromatograms of Wistar rat supraoptic-nucleus extracts, but no evidence of [35S]neurophysin in this fraction was obtained from h.p.l.c. fingerprinting of its S-carboxymethylated tryptic digests. Radioimmunoassay for rVP-Np and rOT-Np revealed that about 70-80% of the total recovered immunoreactive neurophysin (IR-Np) in the supraoptic nucleus eluted from Sephadex G-75 and h.p.l.c. in the positions of rVP-Np and rOT-Np. Evidence is presented for an approx. 20000-mol.wt. rOT-Np in both Wistar and Brattleboro rats and for an approx. 20000-mol.wt. component in the Brattleboro rat that is recognized by vasopressin-neurophysin antisera.
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PMID:Precursors in the biosynthesis of vasopressin and oxytocin in the rat. Characteristics of all the components in high-performance liquid chromatography. 715 2

The synthesis and biological activities of arginine-vasopressin analogues are described, where p-azido-L-phenylalanine [Phe(pN3)] or p-(bromoacetylamino)-L-phenylalanine [Phe-(pNHCOCH2Br)] replace Tyr2 or Phe3. The hormone analogues are prepared via precursors containing p-aminophenylalanine [Phe(pNH2)] in position 2 or 3. During peptide synthesis the p-amino group of [Phe(pNH2)] is protected by the tert-butyloxycarbonyl or the benzyloxycarbonyl group, the side chains of cysteine and arginine by the acetamidomethyl residue and the tosyl group, respectively. The amino and guanidino protecting groups are removed from the nonapeptides by trifluoromethanesulfonic acid yielding the S-protected derivatives which are cyclized by means of iodine. The ring closure by disulfide formation is confirmed by Edman degradation, CD and 1H-NMR spectroscopy. Modification at the p- and alpha-amino groups result in [Phe(pN3)2]-vasopressin, [Phe(pNHCOCH2Br)2]vasopressin, Nalpha-dansyl-[Phe(pN3)2]vasopressin, [Phe2,Phe-(pN3)3]vasopressin and [Phe2,Phe(pNHCOCH2-Br)3]vasopressin. The analogues modified only in position 2, [Phe(pN3)2]vasopressin stimulate the adenylate cyclase derived from bovine kidney inner medulla to similar maximal velocities as arginine vasopressin and show high apparent affinities for enzyme activation. The Nalpha-dansyl derivative and the analogues with reactive groups in position 3 have reduced maximal velocities and apparent affinities for vasopressin-sensitive adenylate cyclase. These results suggest that especially the derivatives with reactive groups in position 2 are useful for the labelling of vasopressin receptors in plasma membranes and for studies of covalent hormone-receptor complexes.
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PMID:Synthesis and biological activities of arginine-vasopressin analogues with reactive groups. 735 40

Cysteine-rich proteins were isolated from the hypothalamo-neurohypophyseal tract of dogs by high performance molecular weight chromatography. Trypsin digestion of these proteins produced a low molecular weight (LMW) peptide which was identified, by chemical and immunological assays, as (Arg8) vasopressin. There appear to be two forms of the precursor protein, one which has vasopressin immunoreactivity, and one which does not. Trypsin digestion of this latter protein produces high as well as LMW immunoreactivity. This suggests that the non-immunoreactive protein may be the precursor to the immunoreactive protein.
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PMID:Direct detection of the vasopressin precursor. 736 54

[35S]Cysteine-labeled putative precursors for vasopressin-associated neurophysin (NP-VP) and oxytocin-associated neurophysin (NP-OT) were isolated from the supraoptic nuclei (SONs) of normal rats. Homozygous Brattleboro rats were deficient in one of these precursors, the NP-VP precursor. Direct support for the hypothesis that OT and its NP- and VP and its NP are synthesized from two separate macromolecular common precursors was obtained by limited proteolysis of the precursors with trypsin and identification of the fragments as NPs, VP, or OT by a number of criteria (14). In this paper, these common precursors designated propressophysin (precursor for NP-VP and arginine VP) and prooxyphysin (precursor for NP-OT and OT) were further characterized. Propressophysin was specifically bound by Concanavalin-A-Sepharose and was eluted by 0.2 M alpha-methyl mannoside, showing that it is glycosylated. In contrast, prooxyphysin does not appear to be glycosylated. Using [3H]fucose as label injected near the SONs, two proteins (mol wt, approximately 10,000) were identified, which appear to be derived from propressophysin, that are rapidly transported to the posterior pituitary of normal rats. These two proteins were absent in homozygous Brattleboro animals. Both propressophysin and prooxyphysin were bound by a NP-Sepharose affinity support. The binding was different from that of arginine VP or OT to NP, since it was independent of pH and was hydrophobic in nature. In addition to prooxyphysin, the SONs of homozygous Brattleboro rats also contained other [35S]cysteine-labeled protein (mol wt, 20,000) composed of a NP-like protein and NP-binding peptides. The tryptic peptides derived from these proteins were very different in their chromatographic (high performance liquid chromatography) properties than the tryptic peptides derived from propressophysin and prooxyphysin. This protein ('X') was not bound by a Concanavalin-A-Sepharose affinity column, although it had chromatographic properties similar to propressophysin on Sephadex G-75.
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PMID:Biosynthesis of vasopressin, oxytocin, and neurophysins: isolation and characterization of two common precursors (propressophysin and prooxyphysin). 742 96

We have determined the primary structure of a novel gamma subunit (gamma 12, previously designated gamma S1) of G protein purified from bovine spleen. The mature gamma 12 protein composed of 68 amino acids had acetylated serine at the N terminus and geranylgeranylated/carboxylmethylated cysteine at the C terminus. This was consistent with the C-terminal prenylation signal in the amino acid sequence, which was predicted from gamma 12 cDNA isolated from a bovine spleen cDNA library. Western blots with the specific antibody against gamma 12 showed that gamma 12 is present in all tissues examined. Among various gamma subunits (gamma 1, gamma 2, gamma 3, gamma 7, and gamma 12), gamma 12 has a unique property to be phosphorylated by protein kinase C. The phosphorylated amino acid residue was Ser1 (or Ser2). The phosphorylated beta gamma 12 associated with Go alpha more tightly than the unphosphorylated form. Exposure of Swiss 3T3 and aortic smooth muscle cells to phorbol 12-myristate 13-acetate and NaF induced phosphorylation of gamma 12. Stimulation of aortic smooth muscle cells with natural vasoactive agents such as angiotensin II and vasopressin also induced phosphorylation of gamma 12. The extent of phosphorylation of beta gamma 12 in vitro was suppressed by a complex formation with Go alpha, which was relieved by the addition of guanosine 5'-O-(3-thiotriphosphate) or aluminum fluoride. These results strongly suggest that gamma 12 is phosphorylated by protein kinase C during activation of receptor(s) and G protein(s) in living cells.
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PMID:Primary structure of a gamma subunit of G protein, gamma 12, and its phosphorylation by protein kinase C. 749 86


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