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)

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

Cadmium, 10(-3) mol/l on the mucosal or 10(-5) mol/l on the serosal side of the toad urinary bladder, inhibits the hydro-osmotic effect of vasopressin. This inhibition is irreversible. The osmotic transfer of water in the absence of vasopressin was unaffected by the presence of the Cd2+. The hydro-osmotic response to cyclic AMP was also reduced by the Cd2+, but the response due to hypertonicity of the serosal bathing solution was unaffected. The short-circuit current (reflecting active transmural Na+ transport) was inhibited by 10(-3) mol Cd2+/l on the serosa, but was increased by 10(-3) mol/l at the mucosa or 10(-4) mol/l at the serosa. The natriferic response of the bladder to vasopressin was unaffected when Cd2+ was present under conditions that inhibited the hydro-osmotic response, further emphasizing that separate effector mechamisms may be involved for each effect.
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PMID:Effects of cadmium of the hydro-osmotic and natriferic responses to the toad bladder to vasopressin. 17 Mar 55

1. Sodium nitroprusside is a potent relaxant of smooth muscles with a predominantly tonic response, e.g. rat aorta contracted by noradrenaline, angiotensin II, Phe2-Lys8-vasopressin, BaC1(2), or KC1, and guinea-pig tracheal smooth muscle contracted by carbachol. 2. Smooth muscle preparations from the splanchnic region and with varying degrees of phasic contractility are less sensitive and develop tachyphylaxis (portal vein, duodenum of the rat) or are unresponsive to sodium nitroprusside (vas deferens, uterus of the rat). 3. Cardiac auricles of the guinea pig are not affected by sodium nitroprusside in either frequency or amplitude or spontaneous contractions. 4. Sdium nitroprusside causes a parallel shift of the dose-response curve of rat aorta to noradrenaline to the right and reduces the maximum response. 5. The drug has no blocking or stimulant effect on alpha- or beta-adrenoceptors, respectively. 6. Sodium nitroprusside inhibits the contractile response of calcium-depleted depolarized rat aorta to extra-cellular calcium. Like verapamil, it inhibits the increment in 45calcium uptake of rabbit aorta elicited by K+. Sodium nitroprusside significantly reduced 45calcium binding by microsomes prepared from rabbit aorta. 7. Rabbit aorta was incubated with lanthanum chloride to prevent calcium influx; sodium nitroprusside reduced the maintained rapid contraction phase in response to noradrenaline which is believed to be based on the intracellular activation of calcium. 8. In rat aorta, cellular cAMP and ATP levels were not found to be affected by the drug. 9. Rabbit aorta, "skinned" by glycerination is unresponsive to sdoium nitroprusside. 10. It is concluded that sodium nitropruside acts on exictation-contraction coupling predominantly in tonic smooth muscle by interfering with both the influx and the intracellular activation of calcium.
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PMID:Mode of action of sodium nitroprusside on vascular smooth muscle. 17 May 45

Studies carried out in both the human and experimental animals provide reasonably strong evidence that receptors contained within the atria are involved in the control of body water. When atrial pressure is increased (and the atria distended) atrial receptor discharge is increased leading to an increase in urine flow and, depending upon the experimental condition, a less consistent increase in sodium excretion. At least two mechanisms appear to contribute to the renal response; inhibition of the secretion of antidiuretic hormone and inhibition of renal nerve discharge. None of the factors presently known to alter sodium excretion have been shown to account completely for the increase in sodium excretion. The failure of patients with chronically distended atria to experience a chronic diuresis appears to be partly the result of a resetting of atrial receptor sensitivity. Recent evidence suggests that the sensitivity of atrial volume receptors has a species variation.
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PMID:The contribution of atrial stretch receptors to salt and water homeostasis in the human. 17 63

The electrical potential difference and short-circuit current (scc, reflecting active transmural sodium transport) across the toad urinary bladder in vitro was unaffected by the presence of hypo-osmotic solutions bathing the mucosal (urinary) surface, providing that the transmural flow of water was small. Vasopressin increased the scc across the toad bladder (the natriferic response), but this stimulation was considerably reduced in the presence of a hypo-osmotic solution on the mucosal side, conditions under which water transfer across the membrane was also increased. This inhibition of the natriferic response did not depend on the direction of the water movement, for if the osmotic gradient was the opposite way to that which normally occurs, the response to vasopressin was still reduced. The natriferic response to cyclic AMP was also inhibited in the presence of an osmotic gradient. Aldosterone increased the scc and Na+ transport across the toad bladder but this response was not changed when an osmotic gradient was present. The physiological implications of these observations and the possible mechanisms involved are discussed.
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PMID:Osmotic inhibition of the natriferic response of the toad urinary bladder to vasopressin. 17 80

Free flow electrophoresis was employed to separate renal cortical plasma membranes into luminal (brush border microvilli) and contraluminal (basal-lateral membrane) fractions. During the separation adenylate cyclase activity was found to parallel the activity of Na+-K+-activated ATPase, an enzyme which is present in contraluminal but not in luminal membranes. In the basal-lateral membrane fraction the specific activities of adenylate cyclase and Na+-K+-activated ATPase were 4.4 and 4.6 times greater, respectively, than in the brush border fraction. The adenylate cyclase of the basal-lateral membrane fraction was specifically stimulated by parathyroid hormone which maximally increased enzyme activity eightfold. The biologically active (1-34) peptide fragment of paratyhroid hormone produced a 350% increase in adenylate cyclase activity. In contrast, calcitonin, epinephrine and vasopressin maximally stimulated the enzyme by only 55, 35 and 30%, respectively. These results indicate that adenylate cyclase, specifically stimulated by parathyroid hormone, is distributed preferentially in the contraluminal region of the plasma membrane of renal cortical epithelial cells.
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PMID:Distribution of parathyroid hormone-stimulated adenylate cyclase in plasma membranes of cells of the kidney cortex. 17 37

We have studied the effects of demeclocycline on the water metabolism of a patient with the syndrome of inappropriate antidiuretic hormone (ADH) secretion who presented with a serum sodium concentration of 110 meq/litre. Free water clearance was studied before, during, and after treatment with demeclocycline. This study shows that demeclocycline (900 mg/day) can at least partially inhibit the action of ADH in the setting of tumor-induced ADH secretion, with the production of a reversible, partial nephrogenic diabetes insipidus, and with few or no side effects. Demeclocycline may be useful in the treatment of chronic inappropriate ADH secretion.
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PMID:Demeclocycline treatment in the syndrome of inappropriate antidiuretic hormone secretion. 17 18

The effects of ethanol on the water permeability and short-circuit current of the isolated urinary bladder of the toad, Bufo marinus, were investigated. Ethanol alone did not alter the flow of water along an osmotic gradient. The increase in osmotic water flow caused by vasopressin, theophylline or cyclic adenosine-3',5'-monophosphate was inhibited by 4 to 40 mg per ml of ethanol in the mucosal or serosal bathing medium. The inhibition was more marked when ethanol was added to the serosal bathing medium, in spite of the increase in the osmotic gradient across the toad bladder caused by the ethanol. Ethanol had no effect on the increase in sodium transport (short-circuit current) due to vasopressin, although there was a significant inhibition of base-line short-circuit current. It is possible that the water diuresis due to ethanol may result in part from an inhibition of the effect of vasopressin on the collecting duct.
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PMID:Effect of ethanol on the water permeability and short-circuit current of the urinary bladder of the toad and the response to vasopressin, adenosine-3',5'-monophosphate and theophylline. 17 29

1 The effect of intravenous infusion of lithium, 2.56 mumol/min on the antidiuretic responses to antidiuretic hormone (ADH), adenosine triphosphate (ATP), 3'-5' adenosine cylic monophosphate (cyclic AMP) and theophyline was studied in water-loaded, alcohol-anaesthetized rats. 2 Lithium reversibly inhibits the antidiuretic response to all concentrations of ADH, depressing the maximum response but not changing the amount required for half maximal response. 3 The rate of increase of serum lithium relates more clearly to the inhibitory effect than does the serum concentration. 4 Sodium concentrations in the renal papilla seem to fall when serum lithium levels are rising. 5 Lithium inhibits the antidiuretic response to ATP and cyclic AMP but does not inhibit the response to theophyline.
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PMID:The effects of lithium ions on the antidiuretic action of vasopressin in the rat. 17 68

The rate of active sodium transport as measured by short-circuit current across the isolated skin of the toad, Scaphiopus couchi, was elevated following vasopressin (0.2 units/ml) or arginine vasotocin (0.1 units/ml) treatment of skins from active animals at all times of the year tested. Skins from dormant animals showed no such elevation at any time of the year. The rate of active sodium transport was elevated following treatment with dibutyryl cyclic AMP (2.5mM) plus theophylline (10 mM) in all skins tested. The hydraulic conductivity of isolated skins from both active and dormant animals showed no significant change following treatment with vasopressin (0.2 units/ml) or arginine vasotocin (0.1 units/ml except on the first day following emergence from dormancy in the field. A correlation was, therefore, observed between the occurrence of a hydroosmotic response to antidiuretic hormones and the seasonal exposure of S. couchi to standing water. A small but significant elevation of hydraulic conductivity was observed across the skins of dormant toads following treatment with dibutyryl cyclic AMP (2.5 mM) plus theophylline (10 mM) whereas a substantial elevation was observed with the skins of active animals.
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PMID:Variation in the effects of antidiuretic hormone on the isolated skin of the toad, Scaphiopus couchi. 17 15


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