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)

Several experimental conditions such as antidiuretic hormone (ADH) challenge, apical treatment with phorbol myristate acetate (PMA), and mechanical stretching of the tissue are known to increase the insertion of intramembrane particle aggregates and/or granule exocytosis at the apical border of epithelial cells of amphibian urinary bladders. A constant release of 2 peptides of 76 and 14 kDa apparent molecular mass, respectively, was associated with these treatments. The localization of these 2 polypeptides was assessed by immunofluorescence and electron microscopy immunocytochemistry using fluorescent, peroxidase, and colloidal gold probes. The 76 kDa polypeptide appeared to be associated with the cell coat and with the granule content which is released at the apical cell surface. The 14 kDa peptide was also found in the cell coat, and postembedding immunocytochemistry indicates its presence in cytoplasmic subapical vesicles (aggrephores and/or granules). The migration of these 76 and 14 kDa polypeptides in SDS-polyacrylamide gel electrophoresis was modified neither by a treatment at 90 degrees C, nor by the presence or absence of calcium in the medium. Treatment with EGTA did not modify the fluorescence emission of the two peptides and, consequently, they are probably not among the major calcium binding proteins. The addition to the mucosal medium of the stretch extract or of antibodies raised against the 76 and 14 kDa peptides did not modify ADH-induced water permeability. However, a significant decrease of the hydrosmotic response to ADH occurred in subsequent stimulation-washout cycles when the anti-14 kDa peptide antiserum was applied to the mucosal bath. When the bladders were incubated with a stretch extract, we observed a slight alteration of the short-circuit current (Isc), an increase of the basal Na+ transport, and a decrease of the maximal Isc in response to ADH. The 76 kDa protein, released in the apical medium, could play a protective role in the cellular plasma membrane and could participate in the formation of the thick cell coat lining the apical membrane of the granular cells. The 14 kDa protein might be one of the proteins associated with the aggregates, but further studies will be necessary to clarify its exact role in the ADH-induced permeability modifications observed in amphibian urinary bladders.
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PMID:76 and 14 kDa polypeptides, two major components released from amphibian urinary bladder epithelium. Localization and potential role. 250 72

Vasopressin V1 receptors were solubilized from rat liver plasma membranes with the detergent lysophosphatidylcholine. [[3H]Arginine]vasopressin (AVP) binding to the solubilized preparations was specific and saturable, with a dissociation constant of 0.6 nM. Cross-linking of [125I]vasopressin to the solubilized fraction, studied by SDS/polyacrylamide-gel-electrophoretic analysis, demonstrated the presence of a 65 kDa band which was specifically labelled with [125I]vasopressin. Specific binding of [3H]AVP to these solubilized receptors was decreased by guanine nucleotides, but not by adenosine 5'-[beta gamma-imido]triphosphate. Addition of vasopressin increased specific binding of 35S-labelled guanosine 5'-[gamma-thio]triphosphate (GTP[35S]) to the solubilized fractions, indicating co-solubilization of GTP-binding protein(s) [G-protein(s)] and vasopressin receptors. The solubilized fraction was insensitive to both cholera- and pertussistoxin treatment. Immunoblotting of the solubilized fraction with antibodies specific for a phosphoinositide-specific phospholipase C (PI-PLC I) demonstrated the presence of a 60 kDa protein. Anti-PI-PLC I antiserum immunoprecipitated solubilized vasopressin-binding sites from rat liver (V1), but not solubilized vasopressin-binding sites from hog kidney (V2). Similar results were obtained with an anti-PI-PLC I IgG affinity column. The solubilized (V1) receptors were enriched by ion-exchange and high-performance gel-filtration liquid chromatography. Vasopressin-binding activity was co-eluted with PI-PLC I and GTP[S]-binding activity on a DEAE-Sepharose column. The major vasopressin- and GTP[35S]-binding activities were co-eluted with PI-PLC I activity at approx. 240 kDa suggesting that vasopressin receptors from rat liver membranes can be solubilized as a complex of receptor-coupler-effector by using the detergent lysophosphatidycholine.
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PMID:Solubilization of rat liver vasopressin receptors as a complex with a guanine-nucleotide-binding protein and phosphoinositide-specific phospholipase C. 254 66

It is now generally accepted that the increase in water permeability induced by antidiuretic hormone (ADH) in responsive epithelia is accompanied by the insertion of specific structures in the apical membrane of epithelial cells. There are strong indications that these particles, probably proteic in nature, represent water channels. In order to evaluate the nature and role of such proteins, plasma membranes were isolated by the affinity chromatography technique. The method is based on the firm attachment of the external face of the membrane to polycations covalently bound to the surface of polyacrylamide beads, followed by shearing of the rest of the cells. Maximal binding of epithelial cells to beads was achieved in a medium of low ionic strength and pH 5.2 (i.e. sucrose-MES buffer). By this procedure plasma membranes were obtained from both cAMP-stimulated cells and control cells. Membranes isolated on beads were enriched in the activity of typical membrane marker enzymes (LAP; H+ ATPase; Na+, K+ ATPase) with respect to a whole cell homogenate, whereas contamination of plasma membrane fraction by endoplasmic reticulum, lysosomes, and mitochondria was relatively low. Analysis by SDS polyacrylamide gel electrophoresis showed an interesting difference between cAMP-treated and control samples.
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PMID:Isolation of frog urinary bladder plasma membranes with polycation coated beads. 280 62

In the amphibian urinary bladder, water permeability is correlated with the insertion of intramembrane particle aggregates (IMPAs) into the apical plasma membrane (AM) of the granular cells. These aggregates are believed to contain water channels. Characterization of the IMPAs by comparing AM fractions of antidiuretic hormone (ADH)-treated and resting epithelia requires isolation and purification of AM-rich material, free of other cytoplasmic aggregate-containing organelles, in both cases. A technique derived from freeze-fracture was chosen to isolate large sheets of apical membrane material from frog (Rana esculenta) urinary bladder epithelium. The apical side was plated on a polylysine-coated glass slide, frozen with liquid nitrogen, and fractured. A nylon mesh was inserted between the glass slide and the bladder, in order to bring the fracture plane back to the AM periodically. Fluorescent markers were used to characterize the material having fractured with the glass slide. Samples were observed by fluorescence and phase contrast microscopy. We obtained evidence that numerous patches of fractured AM remained on the glass surface without nuclei. A phase contrast picture was obtained only at a high magnification, indicating a low thickness of the recovered material. Further characterization was made with SDS-PAGE. Protein contents of samples were extracted under various experimental conditions and the patterns of ADH-treated, resting AM samples, or whole epithelial cell crude homogenates, were compared. Staining of some bands increased under certain conditions, whereas many others disappeared. Both morphological and biochemical approaches demonstrate that the recovered material was apical in origin.
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PMID:Isolation of large sheets of apical material from frog urinary bladder epithelial cells by freeze-fracture. 280 63

Atrial natriuretic factor (ANF) specifically stimulated the endogenous phosphorylation of a protein band in an isolated membrane fraction of human placenta. The apparent molecular weight of the substrate protein as determined by SDS-polyacrylamide gel electrophoresis is 160-170,000. In the same membrane fraction, ANF also stimulated guanylate cyclase activity in a dose-dependent manner. Guanosine 3':5'-cyclic monophosphate (cyclic GMP), added to the membrane fraction in lieu of ANF, also stimulated the phosphorylation of several protein bands, one of which have the same apparent molecular weight as the one stimulated by ANF. In contrast, adenosine 3':5'-cyclic monophosphate (cyclic AMP) at a similar concentration and hormones such as angiotensin II, insulin and vasopressin had no effect on the phosphorylation state of this protein band. The finding that ANF alters the phosphorylation state of a certain membrane protein and that this effect is mimicked by cyclic-GMP suggests that at least some of the biological action of ANF may be mediated by the phosphorylation of membrane protein involving a cyclic GMP-dependent protein kinase.
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PMID:Atrial natriuretic factor induced phosphorylation of human placental membrane protein: an effect mimicked by guanosine 3':5'-cyclic monophosphate. 287 3

The apical plasma membrane of epithelial cells of frog and toad urinary bladder is subject to large modifications during the induction of water permeability by the antidiuretic hormone. A better characterization of the apical membrane is necessary for a clear understanding of the mechanisms of hormone action. Towards this end, apical material was extracted by enzymatic treatment and by incubation with detergent. Proteolytic enzyme alone had little effect under our conditions. A pretreatment with several glycosidases (alpha-mannosidase or endo-beta-N-acetylglucosaminidase H) increased the hydrolytic action of papain, elastase, proteinase K or Staphylococcus aureus V8 protease and allowed the detection of a major 76 kD in SDS gel electrophoresis. The n-octyl-beta-D-glucopyranoside (0.2%) led to the extraction after 150 mn of 1 to 5 micrograms proteins per cm2 of amphibian urinary bladder apical surface. The extracted proteins migrated as several bands on SDS gels. One of them probably corresponds to the 76 kD fragment obtained after proteolysis. The absence of alteration of the water permeability after extraction and the good preservation of the ultrastructure are evidence for the localisation of the 76 kD at the apical membrane surface. This protein may be the best candidate as antigen to raise antibodies against the apical surface of amphibian urinary bladder epithelial cells.
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PMID:Apical material extracted from amphibian urinary bladder epithelium by enzymes and detergent treatment. 293 6

Adenylate cyclase activity in renal papillary membranes was stimulated by both vasopressin and the adenosine agonist 5'-N-ethylcarboxamidoadenosine (NECA). The stimulations mediated by the two receptors were additive at all concentrations and interacted differently with other AC-stimulatory factors viz cholera toxin, pertussis toxin and fluoride ion. Treatment of papillary tubules with cholera toxin increased cyclase activity from 4.5 +/- 1.5 to 110 +/- 9.1 (SE, n = 5) pmol/min/mg protein. Maximally effective concentrations of vasopressin increased activity in control preparations to 10.3 +/- 2.8 (an increase of 5.8 +/- 1.3). In cholera toxin treated preparations, vasopressin increased activity to 138.9 +/- 14.5 (an increase of 28.9 +/- 5.4, n = 5; p less than .01). Pertussis toxin increased activity to 9.1 +/- 3.0. The response to vasopressin was enhanced such that the absolute maximum increase in activity was 12.6 +/- 3.9 (n = 5; p less than .01). Addition of the two toxins together produced a greater than additive stimulation to 145 +/- 36. Maximum increase in activity caused by vasopressin was further enhanced to 48 +/- 13 (n = 5; p less than .01). In contrast, cyclase stimulation by NECA was additive with stimulations by the two toxins, separately and in combination. The NECA stimulation however, was enhanced in the presence of fluoride ion while the vasopressin stimulation was additive at all concentrations. Papillary membranes contained two different cyclase-stimulatory coupling proteins with alpha-subunits of MW's 46,600 +/- 450 (SE, n = 6) and 41,500 +/- 480 (SE, n = 6) as identified on SDS-polyacrylamide gel electrophoresis following cholera toxin labeling. Taken together, these data suggest that two adenylate cyclase-stimulatory coupling mechanisms with different properties are operative in renal papillary membranes.
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PMID:Evidence for two different stimulatory adenylate cyclase coupling mechanisms in rat renal papilla. 294 38

The binding of vasopressin, angiotensin II and prazosin (alpha 1-adrenergic antagonist) to purified heavy (GH) and (intermediate + light) (GI + L) rat liver Golgi fractions was studied. The three types of ligands showed a saturable and specific binding in Golgi fractions; the maximal specific binding of [3H]vasopressin, [3H]prazosin and [125I]Sar-N3-Phe-angiotensin II was respectively 5-10%, 20-30% and 30-40% of that detected in purified plasma membranes. The apparent binding affinities of the three ligands were the same whether determined in Golgi fractions or plasma membranes. The presence of vasopressin, alpha 1-adrenergic and angiotensin receptors in very different proportions, as compared to the amount of receptor detected in plasma membranes, in GH and GI + L Golgi fractions was not compatible with the idea that a plasma membrane impurity accounted for the detection of receptor in the purified intracellular particulate fractions. In vivo injection of [125I]Sar-N3-Phe-angiotensin II resulted in a receptor-mediated endocytosis of the iodo-angiotensin analog into the GH and GI + L Golgi fractions. The apparent molecular weight of the irreversible complex, [125I]angiotensin-receptor, was estimated in subcellular fractions using SDS-PAGE electrophoresis. This value was identical after either in vivo or in vitro labelling (MW = 63,000) and was indistinguishable from the molecular weight of the irreversible hormone receptor complex present in the plasma membranes.
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PMID:Vasopressin, angiotensin and adrenergic receptors of rat liver Golgi fractions--molecular weight of the angiotensin-receptor irreversible complex after in vitro and in vivo labelling. 295 70

The possibility of covalently attaching vasopressin to its receptors by the use of a bifunctional reagent was explored. Plasma membranes from the LLC-PK1 pig kidney cell line were purified by Percoll density gradient centrifugation. These membranes contained a single population of high affinity (Kd = 5.2 nM) and high capacity (Bmax 3.8 pmol/mg of protein) [3H]lysine vasopressin ([3H]LVP)-binding sites. [3H]LVP-labeled receptors could be solubilized with a high yield (83%) and minimal dissociation (9%) by treatment with the non-ionic detergent, octaethylene glycol mono-n-dodecyl ether (C12E8) (0.5%, v/v) in the presence of glycerol (20%). The solubilized [3H]LVP-labeled receptors were stable upon storage at 4 degrees (5% dissociation after 24 hr). They were partially purified to a specific activity of 17 pmol/mg of protein by chromatography on a Cibacron blue-Sepharose column with a yield of 90%. The [3H]LVP-receptor complexes in both intact membranes and the partially purified preparation were almost completely dissociated by incubation at 30 degrees for 30 min in the presence of 20 mM ethylenediaminetetraacetate (EDTA). This property was used to test the effect of ethylene glycol bis (succinimidyl-succinate) (EGS) as cross-linking reagent for the covalent attachment of [3H]LVP to its receptors. After treatment of [3H]LVP-labeled membranes for 30 min with 1 mM EGS at 4 degrees, about 30% of specifically bound [3H]LVP was resistant to EDTA dissociation. The amount of EDTA-resistant binding varied as a linear function of the fractional receptor occupancy and maximal binding capacity of the different batches of membranes used. Similar results were obtained with solubilized and partially purified vasopressin receptors. Upon steric exclusion high performance liquid chromatography, the EDTA-resistant [3H]LVP-labeled material, like the native [3H]LVP-labeled receptor, was eluted as a single and apparently homogeneous peak. The covalent character of the EGS-induced [3H]LVP binding to solubilized or partially purified receptors was assessed by its resistance to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The yield of EGS-induced labeling deduced from these experiments (27%) was close to that determined by the EDTA method. SDS-PAGE analysis of the [3H]LVP-labeled cross-linked material revealed the specific labeling of a major 50-kDa component and a minor component of 30 kDa. The size of these two components was not affected by dithiothreitol.
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PMID:Covalent labeling of vasopressin receptors from LLC-PK1 cells by the use of a bifunctional reagent. 296 89

Radioiodinated synthetic atrial natriuretic factor (ANF) bound to a single class of high affinity binding sites in the plasma membrane from bovine adrenal cortex with a KD of 7.4 X 10(-10) M. The binding affinities of related peptides showed close parallelism to their potencies in natriuretic and vasorelaxant activities. Incubation of adrenal membranes with radioiodinated 4-azidobenzoyl ANF or a similar derivative of its analogue followed by photolysis resulted in specific radiolabeling of a protein band in SDS gel electrophoresis with an apparent Mr of 124,000 in bovine or Mr of 126,000 in rat, which was abolished by inclusion of unmodified ANF in the incubation. Prevention of the labeling was dependent on the concentration of ANF and was not observed with atriopeptin I or with unrelated peptides, angiotensin II, ACTH or [Arg8] vasopressin. These results indicate specific covalent labeling of ANF-receptor or its subunit by the photoaffinity ligands.
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PMID:Photoaffinity labeling of atrial natriuretic factor receptor in bovine and rat adrenal cortical membranes. 299 13


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