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)

1. Cytidine-5'-monophospho-N-acetylneuraminic acid: (galactosyl-N-acetyl-galactosaminyl-(N-acetylneuraminyl)-galactosyl-glucosylceramide sialyltransferase (CMP-NAcNeu: monosialoganglioside (GM1) sialyltransferase) activity was demonstrated in the neurohypophysis of the rabbit. 2. Optimum activity occurred at pH 6.5 and required the presence of exogenous galactosyl-N-acetylgalactosaminyl-(N-acetylneuraminyl)-galactosyl-glucosylceramide (GM1 ganglioside), detergent (Triton X-100), and divalent cation (Mn2+, Mg2+ or Ca2+). 3. The product of the reaction was characterized as N-acetylneuraminyl-galactosyl-N-acetylgalactosaminyl-(N-acetylneuraminyl)-galactosyl-glucosylceramide (GD1a) by ascending thin-layer chromatography. 4. Physiological stimulation of vasopressin secretion, by the substitution of 2.2% NaCl for drinking water for 14 days, had no effect on the enzyme activiity or the ganglioside content of the tissue.
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PMID:Cytidine-5'-monophospho-N-acetylneuraminic acid galactosyl-N-acetylgalactosaminyl-(N-acetylneuraminyl)-galactosyl-glucosylceramide sialyltransferase in the neurohypophysis of the rabbit. 0 25

Adenylate cyclase and the [8-lysine]vasopressin receptor were solubilized from pig kidney medulla membranes using the nonionic detergent Triton X-100. Optimal conditions for solubilization were under continuous stirring in a medium containing 0.5% (/v) Triton X-100, 100 mM Tris-HCl, pH 8, and 10 mM MgCl2. Both adenylate cyclase activity and [3H][8-lysine]vasopressin binding activity were recovered in a -26,000 X g supernatant of detergent-treated membranes. The yield of solubilized adenylate cyclase was nearly 100%. The soluble enzyme was no longer sensitive to antidiuretic hormone but was slightly activated by sodium fluoride. The affinity of the soluble receptor for [8-lysine]vasopresin was les than that of the membrane-bound receptor (mean apparent Km values, respectively 10(-7) M and 2 X 10(-8) M), however binding cooperativity was preserved. Hill coefficients were 1.42 for the soluble receptor and 1.50 for the membrane receptor. The soluble receptor discriminated as efficiently as did the membrane receptor between [8-lysine-a1vasopressin and oxytocin. The yield of spolubilized receptor was only 30% despite the fact that all binding activity had disappeared from the residual pellet of detergent-treated membranes. When the membranous receptors were occupied before solubilization and the latter was performed under conditions in which dissociation of the hormone-receptor comples is slow, i.e. at low temperature, 65% to 100% of the hormone-receptor complex was recovered in the soluble fraction. The soluble hormone-receptor complex partially dissociated on rewarming whereas the free hormone concentration was kept unchanged in the medium. The residual binding capacity, which was 30% of the initial value, was identical with that determined when the receptor was solubilized in free form before incubation with labeled hormone. It was concluded that (a) solubilization of the receptor molecules was complete, (b) during solubilization two forms of the receptor appear, of which only one is accessible to the hormone, (c) occupancy of the receptor by the hormone prevented the formation of the nonaccessible form, and (d) some component or components of the soluble fraction might be responsible for the loss in apparent affinity.
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PMID:Solubilization of the [8-lysine]vasopressin receptor and adenylate cyclase from pig kidney plasma membranes. 17 Feb 74

It is clearly established that the changes induced by antidiuretic hormone (ADH) in its target epithelial cells result from the insertion in the apical membrane of new components that contain channels for water. We have already undertaken an initial study of these channels by raising polyclonal antibodies against Triton X-100 apical extracts from ADH-treated bladders and approached their purification by different adsorption steps. In the present study, we used the label-fracture technique to investigate the localization of the binding sites of the obtained polyclonal antibodies on the apical membrane of ADH-stimulated frog urinary bladder. The results obtained clearly demonstrated a preferential labeling by the selected antibodies of morphological structures such as the groove arrays and the fusion images that are generally accepted as being involved in ADH-induced changes in water permeability of the apical membrane.
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PMID:Selected polyclonal antibodies and ADH challenge in frog urinary bladder: a label-fracture study. 137 49

We studied the effect of ethanol on the phosphorylation of cytokeratins (CKs) in cultured hepatocytes since CK filaments are regulated by phosphorylation and they are abnormal in alcoholic liver disease. Hepatocytes were obtained from 14-day-old rats and cultured for 48 hrs. The hepatocytes were exposed to ethanol (300 mM) for 30 min. The cells were extracted with the buffer containing Triton X-100. The residual insoluble cytoskeletons were analyzed by two dimensional (2D) gel electrophoresis and autoradiography. 2D gel electrophoresis showed CK 55 and CK 49 or 8 and 18 and actin. The CKs had several isoelectric variants. The most basic spot was the dominant protein which was not phosphorylated. The more acidic spots were phosphorylated. After ethanol treatment, the phosphorylation of CK 55 and CK 49 were markedly increased over controls. We compared these results, with the effect of vasopressin (10 nM), TPA (150 nM) and db-cAMP (1 mM) on the phosphorylation of CKs. Vasopressin and TPA caused the phosphorylation of CK 55 and 49 but db-cAMP did not. The results suggest that CKs are phosphorylated by protein kinase C through the phosphoinositide-linked transduction system activated by ethanol.
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PMID:Ethanol-induced phosphorylation of cytokeratin in cultured hepatocytes. 169 3

Detergents (Triton X-100, dodecyl sulphate, saponin) added in concentrations of 0.1-10 mg/ml to solution at the outer frog skin surface reversibly reduced potential difference (PD) and short-circuit current (Isc); when added at the inner surface. Triton X-100 initially induced a short increase in the PD and Isc followed by a pronounced decrease similarly as after the application of any of the detergents used. When added to either serosal or mucosal surface of frog urinary bladder, the detergents reversibly abolished the reactivity to vasopressin. Triton X-100 blocked foskolin and cAMP-induced effects on membrane water permeability. The results suggest that hydrophobic elements of membrane play a crucial role in the regulation of membrane permeability for ions and water and of the responsiveness of the cells to vasopressin. Differences in sensitivity to detergents could be observed between the apical and the basolateral cell membrane.
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PMID:Reversible inactivation of water and sodium transport systems in frog urinary bladder and skin in the presence of detergents. 214 55

We have studied the effects of vasopressin on isolated cat papillary muscle both before and after damaging the endocardium. The experiments were performed in physiological conditions of temperature (35 degrees C) and calcium concentration (1.25 mM Ca2+). Isometric and isotonic twitches as well as maximal unloaded velocity of shortening (Vmax) were measured. In muscles with an intact endocardium (n = 13), vasopressin (10(-12) to 10(-6) M) induced early twitch relaxation with a significant reduction of time to half isometric tension decline and with concomitant significant decrease in peak twitch performance. In a second group of muscles (n = 13) the endocardial endothelial surface was damaged by briefly (1 s) exposing the muscles to a 0.5% Triton X-100 followed by abundant wash with Krebs-Ringer solution, thereby irreversibly decreasing time to half twitch relaxation and peak twitch tension without significantly affecting Vmax. After this intervention, vasopressin had a positive inotropic effect with a significant increase in peak twitch tension and Vmax with no significant changes in twitch duration. Accordingly, in the presence of a functional endocardium, the direct myocardial positive inotropic effect of vasopressin was reversed, with early twitch relaxation and diminished peak twitch performance. At the highest concentrations of vasopressin, vasopressin-induced functional and morphological damage of the endocardium was observed.
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PMID:Role of endocardial endothelium in positive inotropic action of vasopressin. 222 Nov 23

Sulfhydryl (SH) reactive reagents, such as eosin derivatives, have been found to be useful in labeling water pathways in red cells. In the present study we used an impermeable SH-reagent, a fluorescent maleimide analogue EMA (eosin-5'-maleimide), in order to identify proteins involved in water permeability response to antidiuretic hormone (ADH). We observed that: 1) EMA (1 mM) mucosal pretreatment did not modify either the basal water flux or the subsequent ADH-induced hydrosmotic response; 2) EMA added to the mucosal bath at the maximum response to ADH, significantly decreased net water flux by about 40%; similar results were obtained when 10(-5) M forskolin was used as a hydrosmotic agent. These results suggest that the inhibitory effect of EMA occurs at a post cAMP step, possibly at the level of the sulfhydryl groups of the water channels themselves. Fluorescence distribution in SDS-PAGE of Triton X-100 extracted proteins from bladder labeled with EMA in both control conditions and under ADH stimulation allowed us to identify apical membrane proteins, labeled during ADH stimulation and not labeled in water impermeable controls. Of particular importance are four proteins of 52, 32-35, 26, 17, kDa. These polypeptides are probably involved in ADH-stimulated water transport and may be components of the water channels.
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PMID:Fluorescence labeling of proteins related to ADH-induced change in frog bladder luminal membrane. 248 79

Adenosine 3',5'-cyclic monophosphate (cAMP)-dependent protein phosphorylation is considered a key step in the cellular action of vasopressin (AVP) to regulate water permeability in collecting tubules. However, the proteins serving as a substrate(s) for phosphorylation in undisrupted cells have not yet been identified. In the present study, we developed a method for investigation of in situ phosphorylation of microdissected segments of medullary collecting tubules (MCT) from rat kidney. Incubation of microdissected MCT segments with low concentrations of saponin, "semipermeabilization," increased permeability of the membrane for ATP but did not allow leakage of macromolecules such as lactate dehydrogenase. This treatment also did not cause major disruption of cell structure, or impairment of AVP-sensitive adenylate cyclase. Incubation of semipermeabilized MCT with gamma-[32P]ATP resulted in incorporation of 32Pi into two major protein bands [band "A" of apparent molecular mass (Mr) approximately equal to 66 kDa, and band "B" of Mr approximately equal to 45 kDa] detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis and subsequent autoradiography. Similar incubation of tubules disrupted by hyposmotic solutions and a stronger detergent Triton X-100 resulted in 32Pi incorporation into multiple protein bands. Incubation of MCT with 1 microM AVP resulted in increased 32Pi radioactivity in band A and decreased 32Pi radioactivity in band B. These findings demonstrate a novel method for identification of endogenous protein substrate(s) for cAMP-dependent protein kinase and other protein kinases and phosphatases that are probably involved in post-cAMP steps in the cellular action of AVP in the intact cells of collecting tubules.
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PMID:In situ phosphorylation of proteins in MCTs microdissected from rat kidney: effect of AVP. 283 21

Specific receptors for atrial natriuretic factor (ANF) have been identified and solubilized in glomeruli from rat kidney. Radioiodinated synthetic ANF (Arg 101-Tyr 126) bound to a single class of high affinity (Kd 27 +/- 24 pM) sites with a density of 390 +/- 230 fmole/mg protein. The binding was time- and temperature-dependent, saturable and reversible. The ANF-receptor complex was not affected by angiotensin II, ACTH or vasopressin. Solubilization with 10 mM 3-[(3-cholamidopropyl)-dimethylammonio]- 1-propane sulfonate (CHAPS) slightly increased the affinity for ANF (Kd 5.0 +/- 3.3 pM) without affecting the density (250 +/- 110 fmole/mg protein). Similar results were found with 1% Triton X-100. ANF-related peptides interact generally in the same way with non-solubilized and solubilized receptors, indicating a fully preserved specificity of the receptors.
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PMID:Partial characterization and solubilization of receptors for atrial natriuretic factor in rat glomeruli. 299 77

Calmodulin-binding proteins present in chromaffin cell plasma membranes were isolated and directly compared with calmodulin-binding proteins present in chromaffin granule membranes. Chromaffin cell plasma membranes were prepared using Cytodex 1 microcarriers. Marker enzyme studies on this preparation showed a nine- to 10-fold plasma membrane enrichment over cell homogenates and a low contamination of these plasma membranes by subcellular organelles. Plasma membranes prepared in this manner were solubilized with Triton X-100 and applied to a calmodulin-affinity column in the presence of calcium. Several major calmodulin-binding proteins (240, 105, and 65 kilodaltons) were eluted by an EGTA-containing buffer. 125I-Calmodulin overlay experiments on nitrocellulose sheets containing both chromaffin plasma and granule membranes showed that these two membranes have several calmodulin-binding proteins in common (65, 60, 53, and 50 kilodaltons), as well as unique calmodulin-binding proteins (34 kilodaltons in granule membranes and 240 and 160 kilodaltons in plasma membranes). The 65-kilodalton calmodulin-binding protein present in both membrane types was shown to consist of two isoforms (pI 6.0 and 6.2) by two-dimensional gel electrophoresis. Previous experiments from our laboratory, using two monoclonal antibodies (mAb 30 and mAb 48) specific for a rat brain synaptic vesicle membrane protein (p65), showed that the monoclonal antibodies reacted with a 65-kilodalton calmodulin-binding protein present in at least three neurosecretory vesicles (chromaffin granules, neurohypophyseal granules, and rat brain synaptic vesicles). When these monoclonal antibodies were tested on chromaffin cell plasma membranes and calmodulin-binding proteins isolated from these membranes, they recognized a 65-kilodalton protein. These results indicate that an immunologically identical calmodulin-binding protein is expressed in both chromaffin granule membranes (as well as other secretory vesicle membranes) and chromaffin cell plasma membranes, thus suggesting a possible role for this protein in granule/plasma membrane interaction.
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PMID:Calmodulin-binding proteins in chromaffin cell plasma membranes. 317 92


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