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)

A guanine nucleotide regulatory protein may be involved in vasopressin-receptor-mediated polyphosphoinositide breakdown in rat liver. Therefore we examined the effects of the non-hydrolysable guanine nucleotide guanosine 5'-[beta gamma-imido]triphosphate (p[NH]ppG) on [3H]vasopressin ([3H]AVP) binding to hepatic plasma membranes and detergent extracts. [3H]AVP bound to a single set of high-affinity binding sites in membranes. Addition of p[NH]ppG decreased the affinity of receptor binding without altering the maximal binding capacity. The rate of dissociation of [3H]AVP from membrane-bound receptors was also enhanced by p[NH]ppG. Solubilization of [3H]AVP-prelabelled membranes with dodecyl beta-D-maltoside resulted in a [3H]AVP-receptor complex that was unstable in solution. Incubation of these extracts for 5 min at 30 degrees C resulted in a 40% loss of bound [3H]AVP, whereas in the presence of p[NH]ppG there was a 54% loss. However, when membranes were prelabelled with [3H]AVP and p[NH]ppG and then solubilized, the resulting hormone-receptor complex was still temperature-labile but insensitive to the further addition of p[NH]ppG. The molecular size of soluble vasopressin receptors was estimated by gel filtration. The [3H]AVP-receptor complex was eluted as a single peak with an apparent molecular size of 258 kDa. However, no peak was detected when solubilized extract was made from membranes prelabelled with [3H]AVP and p[NH]ppG, suggesting that this receptor complex had dissociated during chromatography. It is possible therefore that the high-Mr complex contains the hormone, its receptor and a guanine nucleotide binding protein.
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PMID:Guanine nucleotide regulation of [3H]vasopressin binding to liver plasma membranes and solubilized receptors. Evidence for the involvement of a guanine nucleotide regulatory protein. 294 38

Alcohol or drug tolerance has been viewed traditionally as a homeostatic response to a direct chemical action of the agent on the neuron. This concept has undergone major modification as a result of recent observations that behavioral and environmental factors can alter markedly the tolerance developed to the same drug regimen. Obligatory task performance under the influence of the drug, classical conditional stimuli in an environment habitually associated with drug administration, previous exposure to a tolerance-producing regimen, and environmental modification of the expression of the drug's effect can all influence dramatically the degree of tolerance produced by a given dosage. Attempts to identify possible cellular mechanisms of tolerance development are illustrated by a review of studies on the relations between ethanol tolerance and changes in the neuronal membrane Na+ -K+ ATPase and its interaction with ethanol and norepinephrine, hippocampal serotoninergic systems and their interaction with a vasopressin derivative, a membrane-bound calcium- and calmodulin- dependent kinase, and hypothalamic-hypophyseal endorphin-producing systems. None of these studies or other similar ones, whether correlational or interventional in nature, has yet provided full and credible explanations of the effects of behavioral and environmental factors on tolerance development. Finding such explanations is the major current challenge in the neurobiology of tolerance.
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PMID:The 1985 Upjohn award lecture. Tolerance, learning, and neurochemical adaptation. 300 93

Atrial natriuretic factor (ANF) (1 microM) markedly increased cyclic guanosine monophosphate (cGMP) content in microdissected glomeruli (35-fold) and in microdissected inner medullary collecting ducts (IMCD) (20-fold). ANF caused little or no increase in cGMP content in other nephron segments. The threshold concentration for increased cGMP accumulation by ANF was 0.1-1 nM in IMCD, which is in the range reported for rat plasma. Sodium nitroprusside (1 mM), which selectively stimulates soluble guanylate cyclase, increased cGMP content in glomeruli but not in IMCD. ANF did not alter cAMP accumulation in the absence or presence of vasopressin (AVP) or parathyroid hormone (PTH) in outer and inner medullary tubule suspensions, or in microdissected proximal convoluted tubules (PCT), medullary thick ascending limbs (MAL) or IMCD. These data are compatible with the hypothesis that cGMP is a second messenger for a physiologic action of ANF in the inner medullary collecting duct. ANF apparently activates membrane-bound guanylate cyclase in this segment.
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PMID:Effects of atrial natriuretic factor on cyclic guanosine monophosphate and cyclic adenosine monophosphate accumulation in microdissected nephron segments from rats. 302 27

We have augmented our previous studies [Storey, Shears, Kirk & Michell (1984) Nature (London) 312, 374-376] on the subcellular location and properties of Ins(1,4,5)P3 (inositol 1,4,5-trisphosphate) phosphatases in rat liver and human erythrocytes. We also investigate Ins(1,3,4)P3 (inositol 1,3,4-trisphosphate) metabolism by rat liver. Membrane-bound and cytosolic Ins(1,4,5)P3 phosphatases both attack the 5-phosphate. The membrane-bound enzyme is located on the inner face of the plasma membrane, and there is little or no activity associated with Golgi apparatus. Cytosolic Ins(1,4,5)P3 5-phosphatase (Mr 77,000) was separated by gel filtration from Ins(1,4)P2 (inositol 1,4-bisphosphate) and inositol 1-phosphate phosphatases (Mr 54,000). Ins(1,4,5)P3 5-phosphatase activity in hepatocytes was unaffected by treatment of the cells with insulin, vasopressin, glucagon or dibutyryl cyclic AMP. Ins(1,4,5)P3 5-phosphatase activity in cell homogenates was unaffected by changes in [Ca2+] from 0.1 to 2 microM. After centrifugation of a liver homogenate at 100,000 g, Ins(1,3,4)P3 phosphatase activity was largely confined to the supernatant. The sum of the activities in the supernatant and the pellet exceeded that in the original homogenate. When these fractions were recombined, Ins(1,3,4)P3 phosphatase activity was restored to that observed in unfractionated homogenate. Ins(1,3,4)P3 was produced from Ins(1,3,4,5)P4 (inositol 1,3,4,5-tetrakisphosphate) and was metabolized to a novel InsP2 that was the 3,4-isomer. Ins(1,3,4)P3 phosphatase activity was not changed by 50 mM-Li+ or 0.07 mM-Ins(1,4)P2 alone, but when added together these agents inhibited Ins(1,3,4)P3 metabolism. In Li+-treated and vasopressin-stimulated hepatocytes, Ins(1,4)P2 may reach concentrations sufficient to inhibit Ins(1,3,4)P3 metabolism, with little effect on Ins(1,4,5)P3 hydrolysis.
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PMID:Dephosphorylation of myo-inositol 1,4,5-trisphosphate and myo-inositol 1,3,4-triphosphate. 303 88

Nerve terminals were isolated from sheep posterior pituitary lobes using a collagenase digestion technique. Freshly dispersed terminals, and terminals cultured for up to 3 days were examined by immunofluorescence microscopy. Immunohistochemical results suggested the presence of immunoreactive-neurophysin, -oxytocin and -vasopressin in membrane-bound structures. Membrane depolarization induced by high concentrations of potassium ions stimulated oxytocin release. This release was attenuated in the absence of calcium ions. The calcium ionophore, A23187, was also an effective stimulator of oxytocin secretion. These data suggest that neurohypophysial nerve terminals prepared by a collagenase dispersion procedure may be suitable for the investigation of posterior pituitary secretion mechanisms.
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PMID:Isolation and properties of sheep neurohypophysial nerve terminals. 309 Apr 71

Vasoactive peptides contain a high proportion of proline residues which make them resistant to hydrolysis by many peptidases. However, post proline cleaving enzyme (PPCE; EC 3.4.21.26), a proline specific endopeptidase which specifically hydrolyzes internal peptide bonds on the carboxyl side of proline residues, has been shown to inactivate numerous vasoactive peptides including angiotensins, kinins, substance P, vasopressin and oxytocin. In order to determine whether PPCE could be involved in vascular metabolism of vasoactive peptides, we carried out localization and characterization studies of PPCE-like activity in hog aorta and mesenteric artery. PPCE was assayed fluorometrically at pH 7.0 using the specific PPCE substrate CBZ-Gly-Pro-4-methyl-coumarinylamide. The subcellular distribution of vascular PPCE was essentially the same as that of the cytosolic marker enzyme lactic dehydrogenase (LDH). PPCE was enriched six-fold in the cytosolic fraction (11.4 +/- 2.7 units/mg) and unlike the plasma membrane-bound proline specific exopeptidase dipeptidyl-(amino)peptidase IV (DAP IV; EC 3.4.14.5), little or no activity could be detected in the microsomal or plasma membrane fractions. Similar to PPCE characterized from other sites, vascular PPCE was stabilized and activated by dithiothreitol and EDTA, and inhibited by DFP, p-chloromercuriphenyl sulfonic acid, L-1-tosylamido-2-phenylethylchloromethyl ketone, Cu++, Ca++, and Zn++. Vascular PPCE was unaffected by inhibitors of trypsin and kallikrein (Aprotinin, ABTI), aminopeptidase M (bestatin, amastatin), neutral endopeptidase (phosphoramidon), angiotensin I converting enzyme (captopril) or carboxypeptidase N (MERGETPA). These data demonstrate that PPCE is present in vascular endothelium and/or smooth muscle.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Vascular, post proline cleaving enzyme: metabolism of vasoactive peptides. 354 18

The human platelet membrane receptor for vasopressin (AVP) has been solubilized with the cholic acid derivative detergent 3-( [3-cholamidopropyl)-dimethylammonio]-1-propane sulfonate. Rapid and simple separation of free tritiated AVP ( [3H]AVP) from the solubilized receptor-hormone complex was done by filtration through polyethylenimine-treated filters. [3H]AVP binds to this soluble receptor with an equilibrium dissociation constant of 11.03 +/- 1.86 nM and a maximal number of binding sites = 288 +/- 66 fmol/mg protein while the corresponding values of the membrane-bound receptor are 1.62 +/- 0.21 nM and 237 +/- 38 fmol/mg of protein, respectively. The Ki value for native AVP derived from competition experiments is 11.02 +/- 2.05 nM for the soluble receptor. Competition experiments with specific vascular and renal antagonists confirm that the solubilized receptor belongs to the V1-vascular subtype.
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PMID:Solubilization of human platelet vasopressin receptors. 380 42

The Ca2+/phosphatidylserine-stimulated protein kinase C (PKC) appears to exist as interconvertible inactive, soluble and active, membrane-bound forms. Changes in the bimodal distribution of PKC induced by diacylglycerol or tumor-promoting phorbol esters have been proposed to regulate the activity of this kinase [Nishizuka, Y. (1984) Nature (London) 308, 693-698]. A rapid microassay for assessment of protein kinase C translocation between cytosol and membranes was developed. This procedure, which relied on the selective digitonin-mediated release of cytoplasmic proteins, eliminated potential homogenization and fractionation artifacts. PKC activity toward histone H1 was determined after limited trypsinolysis, which abolished the Ca2+/phospholipid requirement of the enzyme and prevented interference by inhibitory proteins. Complete translocation of PKC to the membrane fraction and subsequent down-regulation of the kinase in response to 12-O-tetradecanoylphorbol-13-acetate treatment of Swiss 3T3 cells could be demonstrated by this method. Platelet-derived growth factor, insulin-like growth factor 1, vasopressin, and prostaglandin F2 alpha facilitated partial conversions of PKC to the membrane-bound form in quiescent 3T3 cells.
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PMID:Rapid microassay for protein kinase C translocation in Swiss 3T3 cells. 382 83

1. Homogenates of neural lobes of bovine pituitary glands were fractionated by differential and density-gradient ultracentrifugation and the distribution of adenosine triphosphatase (ATPase) activity was studied. It was shown that all the activity was membrane-bound. 2. On the basis of ionic requirements the ATPase activity was grouped into three categories: (a) Mg(2+)-dependent, (b) Ca(2+)-dependent and (c) Mg(2+)+Na(+)+K(+)-dependent (ouabain-sensitive) ATPases. The activity in the absence of bivalent cations was negligible. The ratio between the activities of the three ATPases varied between the different subcellular fractions. 3. Preincubation of the subcellular fractions with deoxycholate increased the activity of the Mg(2+)+Na(+)+K(+)-dependent enzyme, whereas the Mg(2+)- and Ca(2+)-activated ATPases were either unaffected or slightly inhibited. Triton X-100 solubilized the Mg(2+)- and Ca(2+)-ATPases; however, the activity of the Mg(2+)+Na(+)+K(+)-ATPase was abolished by the concentration of Triton X-100 used. 4. All the subfractions displayed unspecific nucleotide triphosphatase activity towards GTP, ITP and UTP. These substrates inhibited the hydrolysis of ATP by all three ATPases. ADP also inhibited the ATPases. 5. Polyacrylamide-gel electrophoresis of extracts containing the Mg(2+)- and Ca(2+)-dependent ATPase activity solubilized by Triton X-100 revealed the presence of two enzymes; one activated by either Mg(2+) or Ca(2+) and the other activated only by Ca(2+). 6. In sucrose density gradients the distribution of vasopressin was different from that of all three types of ATPases. It is therefore suggested that the neurosecretory granules do not possess ATPase activity.
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PMID:Adenosine triphosphatase activity in the neural lobe of the bovine pituitary gland. 428 6

Adenosine 3':5'-monophosphate (cyclic AMP) caused a decrease in the net rate of incorporation of radioactive phosphate into a specific protein (protein D) in a membrane fraction from toad bladder. Moreover, when the membrane protein was prelabeled with radioactive phosphate, cyclic AMP caused an increase in the net rate of removal of radioactive phosphate from this specific protein. Certain agents were shown to be selective inhibitors of membrane-bound protein D kinase or protein D phosphatase. With the help of these agents, it was concluded that cyclic AMP caused the activation of membrane-bound protein D phosphatase. The present data, together with earlier studies, are compatible with the possibility that the cyclic AMP-induced activation of a membrane-bound phosphoprotein phosphatase in toad bladder, with the consequent dephosphorylation of protein D, may be responsible for the physiological effects of antidiuretic hormone on sodium and/or water transport in this tissue.
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PMID:Activation by adenosine 3':5'-monophosphate of a membrane-bound phosphoprotein phosphatase from toad bladder. 435 57


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