Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activities of enzymes related to the cellular action of vasopressin as well as the activities of other enzymes were studied in an animal model of hypothalamic diabetes insipidus. Rats with hereditary hypothalamic diabetes insipidus (homozygotes of Bratteboro strain) were found to have significantly lower renal medullary adenylate cyclase activity, either basal activity or activity stimulated by vasopressin, as compared with controls (heterozygotes of the same strain). There were no differences between the two strains in the activities of cyclic AMP phosphodiesterase, other hormone-sensitive adenylate cyclases, or the other renal medullary enzymes studied, which are apparently unrelated to the vasopressin action. The treatment of rats with hereditary hypothalamic diabetes insipidus with exogenous vasopressin increased the activity of renal medullary adenylate cyclase stimulated in vitro by maximal doses of vasopressin, but had no effect on the basal activity of adenylate cyclase or on the activity of cyclic AMP phosphodiesterase. This suggests that low adenylate cyclase activity in the renal medulla of rats with diabetes insipidus may be related to the subnormal concentrating ability observed in these animals.
 ...
PMID:Renal medullary adenylate cyclase in rats with hypothalamic diabetes insipidus. 17 17

Vasopressin increases the permeability of the total urinary bladder, an analogue of the mammalian renal collecting duct, to water and small solutes, especially the amide urea. We have observed that three general anesthetic agents of clinical importance, the gases methoxyflurane and halothane and the ultrashortacting barbiturate methohexital, reversibly inhibit vasopressin-stimulated water flow, but do not depress permeability to urea, or the the lipophilic solute diphenylhydantoin. In contrast to their effects in vasopressin-treated bladders, the anesthetics do not inhibit cyclic AMP-stimulated water flow, consistent with an effect on vasopressin-responsive adenylate cyclase. The selectivity of the anesthetic-induced depression of water flow suggests that separate adenylate cyclases and cyclic AMP pools may exist for control of water and urea permeabilities in to toad bladder. Furthermore, theophylline's usual stimulatory effect on water flow, but not its effect on urea permeability, was entirely abolished in methoxyflurane-treated bladders, suggesting that separate phosphodiesterases that control water and urea permeabilities are present as well. We conclude that the majority of water and urea transport takes place via separate pathways across the rate-limiting luminal membrane of the bladder cell, and that separate vasopressin-responsive cellular pools of cyclic AMP appear to control permeability to water and to urea.
 ...
PMID:Selective inhibition of osmotic water flow by general anesthetics to toad urinary bladder. 18 13

Many hormones initiate their biologic actions by augmenting the intracellular concentrations of 3',5'-adenosine monophosphate (cyclic AMP). The nucleotide has been found in body fluids; its determination in plasma and urine can be performed by a rapid, simple and specific method: the cyclic AMP assay kit of the Radiochemical Centre (Amersham, England). The assay is based on the competition between unlabelled cAMP and a fixed quantity of the tritium labelled compound for binding to a bovine muscle protein which has a high specificity and affinity for cAMP. Different factors must be considered in evaluating the 24 h urinary content of the nucleotide: the renal or extrarenal origin of cAMP and the functional status of the kidneys. In basal conditions the urinary cAMP excretion is significantly correlated with creatinine excretion (n = 67; r = 0.47; p less than 0.001) thus confirming that the most part of cAMP excreted is derived from the plasma by glomerular filtration. Parathyroid hormone (PTH) stimulates adenylate cyclase predominantly in the renal cortex, whereas vasopressin (ADH) stimulated the enzyme in the medulla; thus PTH and ADH could increase the amount of cAMP in the urine from the renal source. In a case of diabetes insipidus and infusion of ADH caused a prompt rise in cAMP urinary excretion. In 5 normals an infusion of bovine synthetic parathyroid hormone caused an increased excretion of cAMP that preceded the phosphaturic response. An infusion of salmon synthetic calcitonin caused a rise in phosphate excretion and no increase in cAMP urinary content. As it concerns the two calciotopic hormones, PTH and CT, it is reasonable to assume that renal receptors are distinct. The 24 h urinary excretion of cAMP in 55 control subjects (3613 +/- 1460 D.S. n moles) was contrasted with the lower excretion in 25 elderly subjects (70-93 years: 1804 +/- 699 n moles), with the high cAMP excretion in a patient with hyperparathyroidism (that fell to normal values following removal of the parathyroid adenoma) and with the low cAMP excretion in patients with primary or surgical hypoparathyroidism. The mean 24 h cAMP excretion in patients with renal insufficiency was significantly decreased when compared to control subjects. These findings and recent reports confirm that the 24 h urinary output of cAMP may be considered an useful index of pharathyroid function in man.
 ...
PMID:[The diagnostic value of the determination of cyclic 3',5'-adenosine monophosphate (cAMP) in urine]. 19 Jun 33

Exogenous cyclic 3',5'-adenosine monophosphate (cAMP) stimulates the effect of the antidiuretic hormone, vasopressin (VP), only in pharmacologic quantities and results have often been inconsistent. The present study examined the ability of a new analogue, 8-[p-Cl-phenylthio]cyclic 3',5'-adenosine monophosphate (C1-PheS-cAMP) to mimic the effect of VP, both biochemically (protein kinase activation) and functionally (hydrosomatic response of perfused collecting tubules) in mammalian kidney tissue. C1PheS-cAMP was found to be about 100 times as effective as cAMP both biochemically and functionally. The increased effectiveness of C1PheS-cAMP is probably is probably due to a greater permeability across the cell membrane and to the resistance of C1PheS-cAMP to enzymatic degradation, Cyclic AMP phosphodiesterase inhibition was observed with C1PheS-cAMP, but its contribution to overall effect was minor. C1PheS-cAMP was found to be more effective than exogenous vasopressin, an effect probably due primarily to its resistance to catabolism. The results provide further new evidence that cAMP and protein kinase are involved in the cellular action of vasopressin. C1PheS-cAMP proved to be a useful tool in the study of hormone action, especially in steps subsequent to cAMP generation.
 ...
PMID:Cyclic AMP in action of antidiuretic hormone: effects of exogenous cyclic AMP and its new analogue. 19 88

PGE1 and PGE2 are known to interfere with the water permeability effect of vasopressin in toad bladder and kidney. It has been proposed that endogenous prostaglandin E (PGE), synthesized within cells of vasopressin-sensitive tissues, serves to modulate the permeability changes elicited by the neurohypophyseal hormone. Direct evidence in support of this hypothesis is as follows: vasopressin increases the biosynthesis of PGE2 in renal interstitial cells and in isolated toad bladder. In the latter, inhibition of vasopressin-induced synthesis of PGE by a variety of inhibitors results in a greater water permeability response to vasopressin. It appears that vasopressin has two effects in toad bladder and kidney: (i) it activates adenylate cyclase thereby increasing the concentration of adenosine 3',5' monophosphate (cyclic AMP), the nucleotide responsible for the resultant increase in water permeability; and (ii) it activates a phospholipase that serves to release arachidonic acid, the precursor of PGE2 from intracellular pools. The PGE derived from the arachidonic acid diminishes adenylate-cyclase activity, in consequence of which the response of the enzyme to vasopressin is modulated.
 ...
PMID:Role of prostaglandin E (PGE) in the modulation of the action of vasopressin on water flow in the urinary bladder of the toad and mammalian kidney. 21 71

The apical (luminal) plasma membrane of toad bladder epithelial cells has been labeled with (125I) diazo-diiodo sulfanilic acid (125I-DDISA) as demonstrated by electron-microscopic autoradiography. The silver grains (125I) were localized exclusively to the apical surface. At concentrations of DDISA of 10(-3) M or less, binding to the apical membrane had no significant effect on the fine structure of the epithelium. At concentrations of DDISA of 10(-6) M or less, the baseline short-circuit current (SCC), and the response to cyclic 3',5'-adenosine monophosphate (cAMP) plus theophylline were unimpaired. At 10(-5) M, baseline SCC was unchanged and the response to cyclic AMP plus theophylline was enhanced. At concentrations of 10(-4) M and greater baseline SCC was depressed and the response to the nucleotide inhibited. The basal-lateral epithelial plasma membranes were labeled by exposing the serosal side to pyridoxal phosphate and reducing the resultant Schiff base with sodium borotritide (3H-NaBH1). In electron-microscopic autoradiographs, the silver grains (3H) were found over the basal and lateral surfaces of the epithelium. At concentrations of pyridoxal phosphate of 10(-4) M and 3H-NaBH1 of 10(-3) M, there were no significant changes in the fine structure of the epithelium. Addition of pyridoxal phosphate (10(-4) M) and NaBH4 (10(-3) M) to the serosal side decreased the baseline SCC significantly but not the response to vasopressin. Covalent attachment of the 125I and the 3H was indicated by resistance to elution in the preparation of the sections for electron-microscopy and the reagent requirements for binding.
 ...
PMID:Differential covalent labeling of apical and basal-lateral membranes of the epithelium of the toad bladder. 81 32

Increases in transepithelial solute permeability were elicited in the frog skin with external hypertonic urea, theophylline, and vasopressin (ADH). In external hypertonic urea, which is known to increase the permeability of the extracellular (paracellular) pathway, the unidirectional transepithelial fluxes of Na (passive), K, Cl, and urea increased substantially while preserving a linear relationship to each other. The same linear relationship was also observed for the passive Na and urea fluxes in regular Ringer and under stimulation with ADH or 10 mM theophylline, indicating that their permeation pathway was extracellular. A linear relationship between Cl and urea fluxes could be demonstrated if the skins were separated according to their open circuit potentials; parallel lines were obtained with increasing intercepts on the Cl axis as the open circuit potential decreased. The slopes of the Cl vs. urea lines were not different from that obtained in external hypertonic urea, indicating that this relationship described the extracellular movement of Cl. The intercept on the ordinate was interpreted as the contribution from the transcellular Cl movement. In the presence of 0.5 mM theophylline or 10 mU/ml of ADH, mainly the transcellular movement of Cl increased, whereas 10 mM theophylline caused increases in both transcellular and extracellular Cl fluxes. These and other data were interpreted in terms of a possible intracellular control of the theophylline-induced increase in extracellular fluxes. The changes in passive solute permeability were shown to be independent of active transport. The responses of the active transport system, the transcellular and paracellular pathways to theophylline and ADH could be explained in terms of the different resulting concentrations of cyclic 3'-5'-AMP produced by each of these substances in the tissue.
 ...
PMID:Actions of external hypertonic urea, ADH, and theophylline on transcellular and extracellular solute permeabilities in frog skin. 108 Jul 96

Basic changes in receptor-controlled platelet calcium metabolism that occur in the early postoperative period under the effect of aggregation-inducing hormones--platelet activation factor (PAF), adenosine phosphate (ADP) and vasopressin--are reviewed. Patients after lung surgery and patients with ischemic heart disease after aortocoronary bypass surgery have been examined. Patients operated on for malignant lung tumours developed increased postoperative sensitivity to ADP, while in patients after aortocoronary bypass surgery the early postoperative period was characterized by decreased sensitivity to PAF and vasopressin.
 ...
PMID:[The status of the receptor-controlled calcium metabolism of the thrombocytes in patients in the early postoperative period]. 176 48

The vasopressin (VP)-induced increase in water permeability in high-resistance, amphibian epithelia is not altered by the abolition of net Na+ flux caused by amiloride added to the apical bathing medium. In this work we looked at the effects on water transport of amiloride added to the serosal medium at a concentration (10(-3) M) known to inhibit Na+/H+ exchange. In urinary bladders of Bufo marinus, amiloride partially blocked the hydrosmotic response to VP. A similar inhibition was found with cyclic adenosine 5'-monophosphate (cAMP) or serosal hypertonicity. We hypothesized that this effect of amiloride could be due to an inhibition of Na+/H+ and/or Na+/Ca2+ antiporters present in the epithelial basolateral membrane and looked at the effects of the diuretic in Na(+)-free media. A similar degree of inhibition of water flow was still found, thus showing that amiloride acts on a cell target other than the antiporters. In toad skin, amiloride did not inhibit the hydrosmotic response to VP and to isoproterenol; however the response to high K+ was significantly reduced. Among the amiloride cell targets described so far, adenylate cyclase and protein kinase A appear to be the best candidates to explain the inhibition of the hydrosmotic response reported here. Direct measurements of intracellular cAMP are needed however to substantiate this hypothesis.
 ...
PMID:Amiloride inhibits the vasopressin-induced increase in epithelial water permeability. 196 23

The humoral hypercalcemia of malignancy factor (also called PTH-related protein or PTHrp) has been shown to produce effects similar to PTH in the kidney, bone, and cardiovascular system. Binding of PTHrp and PTH has been characterized in renal and osseous tissues, but not in vascular tissue. We have attempted to characterize the interaction of both human PTHrp and rat PTH to renal microvessels as a model of vascular smooth muscle and in a renal tubule preparation from the same rabbit kidneys. Previous studies have shown the microvessel and tubule preparations to be distinct based upon morphological examination, differential enzyme markers, calcitonin and vasopressin-sensitive adenylate cyclase distribution, and different characteristics of guanine nucleotide and of oxidized PTH activation of the adenylate cyclases associated with the preparations. Human PTHrp and rat PTH were iodinated by standard techniques and purified by HPLC. Both ligands bound to microvessels and tubules in a saturable, specific manner, Maximal specific binding of either ligand was 65-75% in microvessels and 80-90% in renal tubules. The time courses of binding of both ligands were identical with steady state achieved within 20 min in the smooth muscle of microvessels and 15 min in the tubules at 22 C. In equilibrium competition binding experiments, bound 125I-PTHrp was displaced by both PTHrp and PTH in microvessels and tubules. Rat PTH displayed slightly higher affinity in microvessels and tubules than PTHrp. Identical results were obtained with 125I-PTH as ligand. Specificity of binding of PTHrp and PTH to both microvessels and tubules was excellent, with competition observed between the radioactive ligand and bovine and rat PTH, PTHrp, and the antagonists, [Nle8,18, Tyr34]bovine PTH and [Nle8,18, Tyr34]bovine PTH but not with several other peptides of unrelated structure. The only major difference in binding between microvessels and tubules was a smaller number of binding sites in microvessels compared to tubules. These results indicate that vascular tissue contains receptor sites for PTH and PTHrp as identified by radioligand binding techniques. These receptors are similar in characteristics to the receptors of renal tubular tissue. Both PTH and PTHrp appear to interact with the receptors of rabbit kidney microvessels and tubules.
 ...
PMID:Binding of parathyroid hormone and parathyroid hormone-related protein to vascular smooth muscle of rabbit renal microvessels. 229 68


1 2 3 4 5 Next >>