Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.1.3 (ATPase)
 65,361 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

Exposure of rats to an ambient temperature of 5 degrees C for 4 to 6 weeks led to a 30 to 80 percent increase in the rate of oxygen consumption and a 50 percent increase in the rate of ethanol oxidation by liver slices, a 50 percent increase in mitochondrial alpha-glycerophosphate oxidase activity of liver, and a 100 percent increase in Na++K+-activated adenosine-triphosphatase, activity. Ouabain, an inhibitor of the Na++K+-activated adenosine-triphosphatase, completely blocked the extra respiration and ethanol oxidation. Dinitrophenol, which increases oxygen consumption and ethanol oxidation by liver slices from normal rats, was ineffective with slices from cold-exposed animals. Ethanol disappearance rate in vivo was also increased by cold acclimation, even though liver alcohol dehydrogenase activity was reduced. It is suggested that increased hydrolysis of ATP by the sodium pump system is responsible for the increased oxygen consumption and ethanol metabolism in the livers of cold-acclimated animals.
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PMID:Ethanol metabolism and liver oxidative capacity in cold acclimation. 12 85

Changes in cardiac metabolism in myocardial failure and after alcohol ingestion are discussed. The main effect of alcohol ingestion is loss of cardiac contractility. Since heart muscle does not contain alcohol dehydrogenase, its toxicity is probably the result of a direct toxic effect of ethanol and acetaldehyde on the myocardial cell, possibly involving various membrane systems. Alcohol inhibits mitochondrial respiration and the activity of enzymes in the tricarboxylic acid cycle, and its interferes with both mitochondrial calcium uptake and binding. Ethanol profoundly affects myocardial lipid metabolism. Acetaldehyde diminishes myocardial protein synthesis and inhibits Ca++-activated myofibrillar ATPase. In myocardial failure, a series of possibilities may be responsible for the loss of contractility. Excitation-contraction coupling could be disturbed at the level of the sarcolemma, at the sarcoplasmic reticulum, at the mitochondria, and between calcium and the regulatory proteins. Deficiencies in Ca++ delivery systems of excitation-contraction coupling on the myosin ATPase activity could be responsible for the dimunition in cardiac contractility. Mitochondrial function may also be involved, since mitochondria from failing human hearts are defective with respect to respiratory control and calcium accumulation. Under certain conditions, the relationship of mitochondria to calcium sequestration is very important in influencing contractility. The involvement of contractile and regulatory proteins in myocardial failure cannot be excluded.
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PMID:Cardiac metabolsim: its contributions to alcoholic heart disease and myocardial failure. 15 68

Ethanol and other alcohols stimulate adenylate cyclase activity in various tissues and potentiate its stimulation by some hormones. This effect, however, usually requires a high alcohol concentration. In some cases, an unknown substance, different from cyclic AMP, was formed from ATP in the presence of an alcohol and mimicked stimulation of adenylate cyclase. Ethanol inhibits phosphodiesterase activity in some tissues. In the brain, only the low affinity enzyme of pons-medulla region is inhibited. ATP levels and ATPase activities are affected by ethanol treatment and this can lead to secondary changes of the cyclic AMP levels. Cyclic AMP levels in the brain and liver are decreased by acute ethanol administration while levels in other organs are unchanged. High doses of ethanol inhibit the postdecapitation-induced rise of cyclic AMP level in the brain while low ethanol doses potentiate the postdecapitation rise of cyclic AMP in the lower brain stem. Chronic ethanol administration increases basal adenylate cyclase activity and cyclic AMP levels, and decreases stimulation of adenylate cyclase by norepinephrine in the brain. In contrast, the stimulation of cyclic AMP formation by norepinephrine and other biogenic amines is increased in the brain of ethanol-withdrawn animals. Chronic administration of ethanol affects also cyclic AMP levels and cyclic AMP formation in some peripheral organs. Cyclic AMP might be involved in ethanol-induced fatty liver, since it activates hepatic lipase and might also participate in the fatty acid oxidation.
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PMID:Interactions of ethanol with cyclic AMP. 16 56

Ethanol, like other anesthetics, has been reported to interfere with active Na+ transport in living membranes. In an attempt to elucidate the mechanism by which ethanol exerts this action, we tested in the toad bladder membrane: 1) the effect of ethanol on active Na+ transport, 2) the interaction of ethanol with vasopressin on Na+ transport, and 3) the effect of ethanol on passive Na+ flux. We found that, a) 1-500 microgram/ml of ethanol stimulated, and 10,000 microgram/ml depressed active Na+ transport; b) the combined effect of stimulating concentrations of ethanol and vasopressin, although suggestive of a positive interaction, might have arisen by chance (p = 0.08); c) depressant concentrations of ethanol failed to suppress the stimulation by vasopressin; and d) passive Na+ flux in bladders treated with ouabain and ethacrynic acid was not affected by ethanol (1-100 microgram/ml). These results indicate that ethanol in concentrations ranging from 1 to 10,000 microgram/ml does not block ATP/ATPase Na+ pump but apparently exerts a dose-dependent, stimulant-depressant effect on Na+ channels in the membrane.
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PMID:Ethanol effects on active and passive Na+ flux in toad bladder. 41 65

The effect of combined administration of ethanol and manganese on the brain tissue of rats was investigated to evaluate the role of alcohol ingestion in inducing susceptibility to manganese poisoning. Ethanol and manganese alone and the combination of the two were administered orally daily to the rats for 30 days. Almost identical increase in the brain contents of manganese in rats receiving the metal alone and in combination with ethanol indicates that ethanol administration does not influence the accumulation of manganese in that organ. The copper contents of brain also increased to almost the same extent in these two groups. Synergistic effect of ethanol and manganese was noticed on increasing the activity of ATPase and RNase while marked antagonistic effect was observed on the activity of MAO. The mechanism and the significance of these neurochemical alterations occurring after the administration of ethanol and manganese have been discussed.
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PMID:The interaction between ethanol and manganese in rat brain. 43 81

Ethanol and acetaldehyde, alone or in combination, at physiologic concentrations, significantly inhibit mitochondrial protein synthesis in vitro. Mitochondria from rats chronically fed ethanol also display a reduced rate of mitochondrial protein synthesis in vitro. This effect is further aggravated by addition of ethanol to the incubation medium. Sodium dodecyl sulfate-gel electrophoresis of mitochondria fractionated with acetic acid-lubrol, which were incubated in the presence of ethanol or acetaldehyde, revealed a modest over-all decrease in labeling. However, a polypeptide fraction in the molecular weight range of 36,000 to 40,000 was conspicuously decreased. This range includes subunits of cytochrome oxidase, cytochrome b, and ATPase. Liver mitochondria from rats fed ethanol chronically showed a comparable decrease in the 36,000- to 40,000-molecular weight peak after incubation with radioactive leucine in vitro and fractionation with acetic acid-lubrol. Similar results were obtained when mitochondrial protein synthesis was determined in vivo in chronically treated rats. The data suggest that chronic ethanol consumption interferes with mitochondrial membrane biogenesis and that several products are more sensitive to this effect than others.
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PMID:The effects of ethanol and acetaldehyde on the products of protein synthesis by liver mitochondria. 50 71

Perfused livers from ethanol pretreated rats utilized ethanol and acetaldehyde at higher rates than appropriate controls. This adaptive increase in hepatic ethanol and acetaldehyde uptake was associated with a marked (greater than 60%) increase in hepatic oxygen uptake. Ethanol uptake in both ethanol-treated and control livers was similarly sensitive to inhibition by 4-methylpyrazole, rotenone, and antimycin A. The adaptive increase in ethanol uptake was apparently specifically abolished by ouabain, an inhibitor of the sodium-plus potassium-activated ATPase. The data are consistent with the hypothesis that chronic treatment with ethanol increases ATPase activity. The ADP produced from these initiating events enters the mitochondrial space and stimulates electron transport and oxygen uptake. As a consequence of these events, a greater rate of NADH reoxidation occurs, resulting in a greater rate of production of NAD+ which stimulates ethanol oxidation via alcohol dehydrogenase and acetaldehyde oxidation via aldehyde dehydrogenase(s).
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PMID:Common mechanism for the adaptive increase in hepatic ethanol and acetaldehyde metabolism due to chronic pretreatment with ethanol. 56 3

1. Theoretical considerations in continuous flow analysis by Walker, Shepherdson and McGowan have been applied to continuous flow radiorespirometry of 14C-glucoses to demonstrate ethanol response differences between water- and ethanol preferring mice. 2. Ethanol dosages in the n mols/kg range stimulated glucose utilization rates more in ethanol-than in water-preferring mice, while intermediate dosages (micron and low mmol/kg) produced equal stimulation but at different dosages. Pharmacological dosages (20-88 mmols/kg) inhibited glucose rates in water-preferring mice. The inhibition was released at 44 mmols/kg in ethanol-preferring mice. 3. Inhibition release was shown to be associated more with glucose carbons other than one, and considered consistent with a sodium-plus potassium-activated ATPase mechanism. 4. Intermediate ethanol dosage changes could be assigned to differences induced in glucose carbon one metabolism with H2O2-catalase and/or microsomal-ethanol-oxidizing systems (MEOS) mechanisms. 5. Our studies suggest that measurements of adenylate deaminase activities might clarify shifts in transaminations (human) and shifts in mononucleotides seen following chronic ethanol ingestion.
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PMID:Ethanol-host interactions determined by radiorespirometry of 14C glucoses. 86 81


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