Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20020 (adenosine triphosphatase)
 3,299 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Treatment with neuraminidase decreased the activity of Na+,K+-activated Mg2+-adenosine triphosphatase in plasma membranes isolated from experimental granulation tissue but not that of 5'-nucleotidase or leucine-beta-naphthylamidase. A temporary lowering of the pH of the plasma membrane suspension to 2-3 inactivated all three enzymes, which remained inactive after the pH had been readjusted to 7.4. Addition of dextran preparations to the membrane suspension decreased the activity of adenosine triphosphatase. Ethanol (0.4%) had a similar effect. These marker enzymes of plasma membranes were not affected by additions of hyaluronate, chondroitin sulfate, protein polysaccharide or soluble collagen. Serotonin stimulated the adenosine triphosphatase activity slightly. About 10-20% of the protein in the plasma membrane preparation was extracted with EDTA. This "fuzzy coat" fraction yielded a distinct gel-electrophoretic protein pattern. Hyaluronidase was not helpful in cleaving this surface layer from the plasma membranes.
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PMID:Properties of plasma membranes from granulation tissue with reference to extracellular matrix. 0 56

The effects of acute and chronic administration of D-Galactosamine (GalN), Ethanol and Phenobarbital were investigated on the activities of lysosomal enzymes, i.e.; acid phosphatase, beta-glucuronidase and n-acetyl-beta-glucosaminidase, and others such as gamma-GTP and adenosine triphosphatase. The histochemical distribution of gamma-GTP in the liver was also studied on biopsy specimens from patients with chronic hepatitis, and gamma-GTP levels in the serum of patients receiving drugs inductable of hepatic microsomal enzymes. 1) After a single intraperitoneal injection of GalN, the lysosomal enzyme activities were lowered in the necrotic areas, but raised in the perinecrotic areas, the proliferative Kupffer cells and intra- and/or extra-cellular eosine bodies. 2) gamma-GTP activities in rat liver after chronic administration of GalN were markedly increased in bile canalicular membrane of periportal parenchymal cells, the epithelium of bile duct and ductules, and som inflammatory cells of portal fields. Levels of serum gamma-GTP were also elevated. On histochemical studies with biopsy specimens from patients with chronic active hepatitis showing elevated gamma-GTP activity, the activity was revealed a similar localization to GalN-treated rats. These data suggested that the increased activities might be reflected on the active stage in chronic hepatitis. 3) Chronic ethanol treatment in rats induced clearly-stained lysosomes varied in size, especially large-sized. The activities of hepatic gamma-GTP were slightly increased in the bile canalicular membrane of periportal parenchymal cells and the epithelium of proliferative bile ductules. 4) It has been shown by histochemical and biochemical techniques that hepatic gamma-GTP activity was increased after phenobarbital administration in rats. A significant rise in serum gamma-GTP was observed in patients on long-term treatment with anti-epileptic drugs. These data indicated that the increased activities of serum gamma-GTP might be accompanied with induction of hepatic microsomal drug-metabolizing enzymes.
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PMID:[Clinical and experimental histochemical studies on the activities of liver lysosomal enzymes and gamma-glutamyl transpeptidase (gamma-GTP) (author's transl)]. 3 25

Ethanol (3%) decreases the potential difference and short-circuit current across the isolated frog skin in chloride Ringer's solution. Unidirectional fluxes of Na and Cl indicate that the drop in short-circuit current is due to an inhibition of the sodium influx. However, ethanol had no effect on the electrical parameters or sodium fluxes, when the frog skin was bathed in chloride-free solutions on both sides or the outside alone. The ethanol response is anion-dependent. In addition, chloride-free media in the inside bathing solution reduced the short-circuit current, indicating a sodium transport pathway which is dependent on chloride and confirming previous data in the literature. Other anions such as sulfate and nitrate could not substitute for chloride. The vasopressin-induced natriferic response and the ethanol effect were found to work independently of each other and different pathways of action are suggested for these agents. The intracellular sodium content of the isolated frog skin epithelium increased and potassium decreased in the presence of the Na-K adenosine triphosphatase inhibitor, ouabain, whereas ethanol or amiloride had no effect. The oxygen consumption of the isolated frog skin was unaffected by up to 10% ethanol. A general metabolic action is probably thus not mediating the response. Urea, in iso-osmotic concentrations to the ethanol, did not mimic its effect. Tritiated water fluxes (in the absence of an osmotic gradient) were reduced by 30% in the presence of 3% ethanol. It is suggested that ethanol may impede the flow of water across frog skin by a physicochemical interaction with membrane pores and the water molecules. The permeability coefficient (Ktrans) for ethanol was found to be 10 times smaller than the Ktrans for water.
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PMID:Effects of ethanol on the permeability of frog skin. 108 5

The effects of pure ethanol and some alcoholic beverages on acid secretion and metabolism were examined in the isolated toad gastric mucosa. Pure ethanol applied to the luminal side or to the submucosal side at low concentrations (2%-10%) was a potent stimulant of acid secretion, whereas high concentrations (greater than or equal to 20%) were inhibitory. Cimetidine and calcium-free solutions did not abolish the secretory effect of ethanol. Beer and wine, but not rum and whisky, caused a significant stimulation of acid secretion. Respiration was progressively increased by ethanol at concentrations between 2% and 20%. This effect was not affected by cimetidine or by SCH 28080, an inhibitor of the gastric hydrogen-potassium-stimulated adenosine triphosphatase. Ethanol (10%) significantly increased by 46% the tissue lactate-pyruvate ratio. The oxidations of glucose, butyrate, and acetate were progressively reduced by low concentrations of ethanol (5% and 10%). The results indicate that (a) low concentrations of ethanol and alcoholic beverages with low ethanol content are direct stimulants of acid secretion and (b) the secretory and metabolic effects of low concentrations of ethanol seem to be mediated via its oxidation.
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PMID:Secretory and metabolic effects of ethanol in the isolated amphibian gastric mucosa. 190 55

Isolated gastric glands from rabbit, as well as basolateral and microsomal membranes derived therefrom, were used to examine the effect of ethanol on several parameters related to acid secretion. Low concentrations of ethanol, 0.2%-5% (vol/vol), had no effect on basal aminopyrine accumulation by isolated gastric glands but significantly potentiated aminopyrine accumulation stimulated by histamine. In contrast, this dose range of ethanol inhibited aminopyrine accumulation stimulated by forskolin or dibutyryl-cyclic adenosine monophosphate. This dose range of ethanol produced a similar effect on adenylate cyclase activity of basolateral membranes from isolated gastric glands, with potentiation of histamine stimulation and inhibition of forskolin stimulation. Low-dose ethanol was found to produce increased proton permeability of the apical membrane of the parietal cell but had no effect on hydrogen-potassium-stimulated adenosine triphosphatase activity. Ethanol (10%) significantly inhibited all parameters of acid secretion studied. Ethanol has a biphasic effect on acid secretion with potentiation of histamine-stimulated aminopyrine accumulation and adenylate cyclase activity at low doses and inhibition of all parameters of acid secretion at high doses.
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PMID:Effect of ethanol on acid secretion by isolated gastric glands from rabbit. 301 11

The effect of chronic alcohol consumption on the extent of adenosine triphosphatase(ATPase)-deficient preneoplastic lesions in rat liver induced by either diethylnitrosamine (DEN) (3 mg/kg, p.o.) or N-nitrosomorpholine (NNM) (40 ppm in the drinking water) was studied. Carcinogens were administered on 4 days in every week for 11 (DEN) and 15 (NNM) weeks, respectively. Ethanol was given at a concentration of 10% (w/v) in the drinking water either during carcinogen treatment or after withdrawal of carcinogen. An increase in both number and size of ATPase-deficient foci in liver was observed when the alcohol was given during the period of carcinogen administration. This increase may be associated with the known toxic action of ethanol which leads to single cell necrosis and liver regeneration. In contrast, when ethanol (10% in the drinking water for 16 weeks) was given after cessation of carcinogen treatment following a tumor-promotion feeding protocol, no such enhancement in preneoplastic response was obtained. Ethanol alone was ineffective in inducing ATPase-deficient foci. In liver, ethanol thus appears to possess, under certain conditions, co-carcinogenic but not tumor-promoting capacity.
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PMID:Effect of ethanol on early stages in nitrosamine carcinogenesis in rat liver. 622 54

The effects of chronic alcohol consumption on nitrosamine metabolism in vivo, DNA synthesis and repair, and carcinogen-induced preneoplasia were studied in rat liver. Following a single injection of different doses of 14C-N-nitrosodimethylamine, there was no significant difference between controls and ethanol-pretreated rats in the alkylation pattern of cellular protein nor in the levels of the alkylation products 7-methylguanine and O6-methylguanine isolated from liver DNA. O6-Methylguanine-specific DNA repair was also unchanged. An increase in the number and size of foci staining negative for adenosine triphosphatase and/or positive for gamma-glutamyltranspeptidase was observed in rats treated intermittently with ethanol and N-nitrosomorpholine. The numbers of clear-cell and mixed-cell foci were also increased. An ethanol-mediated enhancement of DNA synthesis, which was ascertained by different methods, may be related to this cocarcinogenic action of the alcohol. Ethanol, however, failed to demonstrate promoting activity. Long-term treatment of carcinogen pretreated rats with ethanol, according to the classical initiation-promotion protocol, had no effect on the incidence of preneoplastic foci in liver.
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PMID:The mechanism of cocarcinogenic action of ethanol in rat liver. 653 12

In vivo ethanol exposure reduces in vitro Na+,K(+)-adenosine triphosphatase (Na+,K(+)-ATPase) sensitivity to ethanol in some animal models, but very little is known about the effects of ethanol on human brain Na+,K(+)-ATPase. Cerebral cortex homogenates from 13 male alcoholic and 9 control subjects were assayed for K(+)-p-nitrophenylphosphatase (K(+)-pNPPase, a measure of Na+,K(+)-ATPase) and Mg(2+)-pNPPase activities at 37 degrees for 20 min in 75 mM imidazole-HCl (pH 7.4), 5 mM p-nitrophenylphosphate, 5 mM MgCl2, and 20 mM KCl, with or without 1 mM ouabain. Native K(+)-pNPPase activites were similar in control and alcoholic brains (61.5 +/- 3.5 vs 55.3 +/- 3.1 nmol/mg/min). In vitro exposure to a near lethal ethanol level (0.5%, or 110 mM) was without effect, whereas 5% ethanol inhibited K(+)-pNPPase activity by about 28% (P < 0.001) in both groups. Both 0.5 and 5% ethanol in vitro significantly stimulated Mg(2+)-pNPPase activity (1-2% and 19-20%, respectively). By comparison, mouse brain K(+)-pNPPase was inhibited significantly by in vitro ethanol, and Mg(2+)-pNPPase activity was unaffected. Ethanol levels attainable in humans may not be sufficient to alter significantly brain Na+,K(+)-ATPase activity.
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PMID:Effects of in vitro ethanol on the brain cation pump in alcoholics and controls. 805 41

Chronic ethanol exposure causes alterations in biologic membranes of different cell types. (Na + K) adenosine triphosphatase (ATPase), a membrane-bound enzyme inhibited by the acute presence of ethanol, increases its activity in rat kidney after chronic ethanol consumption. The aim of this investigation was to evaluate the effect of ethanol on the modulation of (Na + K)-ATPase by glucocorticoids and mineralocorticoids in renal papillary collecting duct cells. Cultured renal papillary collecting duct cells were exposed to a medium containing 150 mM ethanol plus either 100 nM aldosterone or 10 nM dexamethasone. Control groups were cultured in the absence of ethanol and/or the hormones. Mg(2+)-ATPase was used as control enzyme. The activity of ATPases was measured by ATP hydrolysis. Ethanol increased the activities of (Na + K)-ATPase and Mg(2+)- ATPase in 29 and 33% of controls, respectively; only (Na + K)-ATPase activity was elevated in the presence of aldosterone or dexamethasone, whereas Mg(2+)-ATPase was unaltered by these hormones. The effects of aldosterone and dexamethasone on (Na + K)-ATPase activity were augmented by ethanol in 50 and 19% of controls, respectively. These results suggest that ethanol treatment enhances the upregulation of (Na + K)-ATPase activity by both aldosterone and dexamethasone, in cultured renal papillary collecting duct cells.
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PMID:Effect of ethanol on regulation of (Na + K)-adenosine triphosphatase by aldosterone and dexamethasone in cultured renal papillary collecting duct cells. 1262 30

The pathologic activation of proteases within the pancreatic acinar cell is a key initiating event in acute pancreatitis. Past studies have suggested that the generation of a low-pH environment is critical to this process. Vacuolar adenosine triphosphatase (vATPase) is a multiprotein complex that transports protons across cellular membranes. Activation of the vATPase requires assembly of the soluble (V(1)) subunits on the membrane subunits (V(0)). It is found that conditions that cause protease activation in the acinar cell also cause assembly of V(1) on V(0). Further, inhibitors of vATPase block this protease activation. Ethanol and butanol sensitize the acinar cell to cholecystokinin-induced zymogen activation; vATPase inhibitors also blocked this activation. Activation of the vATPase may be central to the pathologic activation of proteases in the acinar cell and may also modulate the sensitizing effects of alcohols.
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PMID:Vacuolar adenosine triphosphatase and pancreatic acinar cell function. 1695 63


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