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 microcellular dispersion procedure for the rat neurohypophysis was developed, comprising tissue softening and dissociation using a special sieving sytringe. In preparatory studies the influence of mesh width, and treatment with trypsin, pronase or collagenase-hyaluronidase was investigated using light and electron microscopy, as well as with microchemistry by means of protein and lactate dehydrogenase activity determinations. Trypsinization gave the best results. In the final adopted procedure, 3 incubated neurohypophyses were sequentially sieved through a 200- and a 50-mum mesh. The resulting 50-mul dispersion was found to contain numerous ultrastructurally well-preserved pinched-off axonal endings (neurosecretosomes), and pituicytes often revealing processes. On the basis of DNA and oxytocin assays 11% of the pituicytes and 28% of the axonal cytoplasm were recovered. Oxytocin immunofluorescence microscopy showed hormone within the neurosecretosomes, but often also in the cytoplasm of pituicytes. Microdensity gradient centrifugation was performed on neurohypophyseal disperions, in order to obtain fractions enriched for neurosecretosomes and pituicytes. Fractions were characterized by means of phase contrast, oxytocin immunofluorescence and electron microscopy, as well as by oxytocin and DNA assays as respective markers. With a 10:14:22% (w/v) Ficoll gradient, fractions were obtained for which the relative purification was by a factor of 4 on the basis of DNA/oxytocin ratios.
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PMID:Enzymic preparation of neurosecretosome- and pituicyte-enriched fractions from the rat neurohypophysis. 18 63

Distribution of glycanohydrolases activity (hyaluronidase, beta-glucuronidase, N-acetyl-beta-D-hexosaminidase) and glycosaminoglycans in different renal zones (papilla, external medulla, cortex) of homo- and heterozygous Brattleboro rats with hereditary defect of antidiuretic hormone synthesis was studied. Content of the glycosaminoglycans in kidney preparations of homozygotes was shown to be minimal as compared with other rodents; at the same time, the activity of glycanohydrolases in the papilla of diabetic rats was comparatively high. Administration of the antidiuretic hormone at physiological doses was followed by the same increase in the enzymatic activity in renal papilla of homo- and heterozygotes, while certain correlation between the urine osmolality and the degree of the enzymes activation was observed.
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PMID:[Glycosaminoglycans and glycan hydrolases in the kidney of rats with hereditary diabetes insipidus]. 295 7

We modified and improved enzyme digestion and density gradient separation procedures to obtain fractions of proximal and distal renal tubules with high yield and viability. Kidneys from two anesthetized adult Wistar rats were flushed with Krebs-Henseleit buffer (KHB) and then perfused in situ with recirculated KHB containing collagenase and hyaluronidase at 125 mmHg. Cortices were excised, minced, and incubated in KHB containing enzymes for 35 min at 37 degrees C. Dissociated tubules were removed at 10-min intervals, rinsed, and placed in KHB containing 10% calf serum, vitamins, and amino acids at 4 degrees C. Separation was achieved by suspending the tissue in 45% isosmotic Percoll layered over an undiluted Percoll cushion and centrifuging. Proximal tubules sedimented near the cushion. Distal segments were isolated in the uppermost bands of a second 35% Percoll separation. Viability was greater than 95% as measured by lactate dehydrogenase leakage and quantitated by oxygen consumption and ATP content. Basal oxygen consumption was greater than 33 nmol O2 X min-1 X mg protein-1 in all fractions and was stimulated by succinate and inhibited by amiloride and ouabain. Basal ATP content averaged 9.7 nmol/mg ATP. An average 3.3-fold separation for the proximal fraction and 24.5-fold separation for the distal fraction was assessed by the enrichment of six specific enzyme markers, with several of the markers indicating separations up to 32-fold. Isolated tubules also displayed functional responses to parathyroid hormone and vasopressin. Distal, but not proximal, segments demonstrated significantly increased adenosine 3',5'-cyclic monophosphate formation with vasopressin.
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PMID:Improved separation method for rat proximal and distal renal tubules. 303 59

Rat renal papillary collecting duct (PCD) cells were isolated using collagenase and hyaluronidase digestion and a three-step low-speed centrifugation. As assessed by binding of the lectin Dolichos biflorus and determination of vasopressin-sensitive adenylate cyclase and Na+-K+-ATPase, the enrichment of PCD cells over a crude papillary cell preparation was 1.8, 2.4, and 1.4, respectively. Microscopic evaluation indicated that the preparation was greater than 90% pure PCD cells. The isolated cells were viable as evident from the high K/Na ratio of intracellular electrolytes measured by electron probe analysis (5.3), from the high ATP/ADP ratio (2.15), and the metabolic response to alterations in Na transport. Exposure to 2 mM ouabain or removal of Na reduced O2 consumption by 25-35%; the uncoupler carboxylcyanide-m-chlorophenylhydrazone more than doubled O2 consumption. In the presence of 14 mM glucose and at a PO2 of 100 Torr the cells produced substantial quantities of lactate. This aerobic glycolysis may account for greater than 20% of the ATP production. In the presence of rotenone, glycolysis increased by 56% and was able to maintain the cellular ATP level at 65% of control. In the absence of any exogenous substrate PCD cells respired normally and had a close to normal ATP content, but lactate production was markedly decreased. These results demonstrate that viable PCD cells can be isolated from rat kidney. At normal PO2 and in the presence of D-glucose the cells show a substantial amount of aerobic glycolysis, although their mitochondrial respiration is not rate limiting. In the absence of glucose the cells derive the majority of their energy from an as yet unidentified endogenous substrate.
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PMID:Purification of rat papillary collecting duct cells: functional and metabolic assessment. 330 74

Classical techniques for studying modulations of microvascular permeability have a time resolution of minutes. A newly developed method allows continuous measurement of the electrical resistance of the microvascular membrane in vivo (Olesen & Crone 1983). The technique exploits microelectrodes impaled into the vascular lumen and is based on cable analysis of the vessel. It was applied to venules on the surface of the frog brain to test the effect on microvascular permeability of a wide variety of substances. The following agents increased ionic permeability reversibly within seconds: 5-hydroxytryptamine, bradykinin, ATP, ADP, AMP, phospholipase A2, arachidonic acid, leukotriene C4, oxygen-derived free radicals, ionophore A23187, and unbound Evans blue dye. An irreversible permeability increase was induced by protamine sulphate, neuraminidase, trypsin, melittin, and snake venoms from Crotalus durissus terrificus and Bothrops atrox. The following substances were without effect within an administration period of 5 min: histamine, epinephrine, putrescine, angiotensin II, vasoactive intestinal polypeptide (VIP), substance P, neurotensin, vasopressin, adenosine, PGE2, PGF2 alpha, prostacyclin (PGI2), leukotriene B4, albumin, heparin, plant cytokinins, hyaluronidase, thrombin, wasp venom. Variations in pH between 5.1 and 8.6 did not change permeability. Three conclusions are drawn from the observations: (1) the permeability of cerebral microvessels can be modulated by specific agents, (2) the agents induced changes in the endothelium within a few seconds, and (3) the rapid permeability increase induced by inflammatory mediators was less than two-fold and reversible within minutes.
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PMID:Substances that rapidly augment ionic conductance of endothelium in cerebral venules. 348 16

The steps of cell reactions which could modulate the effect of the antidiuretic hormone (ADH) were investigated in experiments on frog urinary bladder. Adrenaline and D2O reduced the interaction between ADH and its receptors. The urinary bladder cells released an inhibitor of ADH changing the reaction of receptors to ADH; adsorption of this inhibitor increased the water permeability after addition of ADH. Increased intracellular concentration of cellular near basolateral membranes produced the increase of water permeability whereas near the apical membranes calcium produced its decrease acting, perhaps, on microtubules. Swelling of the cells caused by ADH didn't change the reaction of these cells to ADH. Nevertheless, the cells swollen in hypotonic solution before the application ADH showed a lesser reaction to ADH. The role of cAMP phosphodiesterase, hyaluronidase, aldosterone, prostaglandins and other physiologically active substances in the action of ADH has been discussed. The data obtained suggest some possible ways and mechanisms of regulation of the cellular action of ADH.
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PMID:[Regulation of the cellular action of antidiuretic hormone]. 628 Oct 92

The effect of antiserum raised against rat urinary (renal) hyaluronidase has been examined in rats subjected to antidiuretic stimuli (water-deprivation or vasopressin infusion). Prior administration of antiserum abolishes the reduction in medullary and papillary extractable hexosamine which normally accompanies antidiuresis. Antiserum against rat testicular hyaluronidase was found to be without effect during water-deprivation. Water-loading significantly increased the level of extractable hexosamine. The findings are considered in relation to previous observations on the effects of antisera on renal and urinary composition and collecting duct morphology under identical experimental conditions. It is suggested that a functional relationship exists between the net degradation of medullary mucopolysaccharides by hyaluronidase and the concentrating capacity of the kidney.
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PMID:Renal medullary hexosamine content following antidiuresis and water-loading in the rat. Effects of antisera against rat urinary and testicular hyaluronidase. 719 63

1. The influence of urinary hyaluronidase (believed to be predominantly of renal origin) on the urinary concentrating process has been studied in rats subjected to antidiuretic stimulus. 2. Antiserum against a partially purified preparation of this enzyme has been raised in rabbits. Urinary volume, solute excretion and medullary composition have been investigated in rats treated with this antiserum (0.2 ml./100 g body weight, i.v.) before water deprivation for 48 hr or infusion for up to 4 hr with arginine-vasopressin. Control rats were pre-treated with normal rabbit serum. 3. Pre-treatment with antiserum against rat urinary hyaluronidase (AUase) caused water-deprived rats to excrete urine at a rate significantly greater, and of osmolality significantly lower, than that recorded in control rats. 4. The increase in medullary solute gradient which typically accompanies antidiuresis was significantly reduced in water-deprived rats pre-treated with AUase. 5. In rats treated with AUase and infused for 4 hr with arginine-vasopressin, there was no significant increase in the medullary solute gradient, whereas this increased markedly in control rats. 6. During the first 24 hr of water deprivation there weas an increase in the rate of Ca excretion by control rats which was abolished by pre-treatment with AUase. 7. The effects of antiserum against a partially purified preparation of rat testicular hyaluronidase (ATase) were studied in water-deprived rats. No evidence was obtained that this enzyme has any influence on renal function. 8. It is concluded that urinary hyaluronidase, but not testicular hyaluronidase, plays an important role in facilitating the urinary concentrating process following antidiuretic stimulus.
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PMID:The influence of hyaluronidase on urinary and renal medullary composition following antidiuretic stimulus in the rat. 726 71

An investigation has been carried out into the formation of dilated lateral intercellular spaces in the medullary collecting duct of the rat kidney following water deprivation or infusion of vasopressin. Dilation is conspicuous under these conditions, by comparison with normally hydrated controls, but its appearance is prevented by prior treatment of rats with antiserum raised against urinary (renal) hyaluronidase. Antiserum against testicular hyaluronidase is without effect. The presence or absence of dilatations in the lateral intercellular space correlates closely with previous findings on the ability or inability of rats to concentrate their urine under identical experimental conditions. It is concluded that urinary (renal) hyaluronidase plays an important role in the formation of such dilatations and that these facilitate the process of urinary concentration.
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PMID:The effect of antidiuretic stimuli on the morphology of the lateral intercellular spaces in the medullary collecting duct of the rat. 733 49

Involvement of enzymes catabolizing hyaluronic acid (hyaluronidase, beta-glucuronidase, N-acetyl-beta-D-hexosaminidase) in the hydroosmotic action of vasopressin on the amphibian urinary bladder Rana Ridibunda was studied. It was found that vasopressin (50 nM), agonist of V2 receptors dDAVP (1.5 mcM) and forscolin (30 mcM) induce an activation of enzymes and its release into the Ringer solution at the mucosal surface simultaneously with the increase in the osmotic water flow. Maximal effect was observed 10 min later than hydroosmotic response. Release of enzymes under vasopressin effect was found in the absence of osmotic gradient and water flow through the epithelium. The repeated substitution of the outer Ringer solution for the fresh one resulted in the increase in the both the water permeability and the release of enzymes through the mucosal surface. We suggested that involvement of hyaluronate-hydrolases in the vasopressin effect is mediated by the cAMP-dependent mechanism. It is supposed that this effect creates conditions for the increase in the permeability of glycosaminoglycan structures covering adjacent to the apical cell surface.
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PMID:[Hyaluronate-hydrolases system and hydroosmotic effect of vasopressin]. 1051 5


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