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)

An initial examination was made of the hypothesis that one action of cigarette smoke components on pulmonary alveolar macrophage function involves the inhibition of contractile protein adenosine triphosphatase activity. Pulmonary alveolar macrophage calcium-dependent adenosine triphosphatase activity, magnesium-dependent adenosine triphosphatase activity, sodium-potassium-dependent adenosine triphosphatase activity, phagocytosis, and cell adhesiveness were measured in the presence of cigarette smoke, acrolein, ouabain, and ethacrynic acid. Calcium-dependent adenosine triphosphatase activity, magnesium-dependent adenosine triphosphatase activity, phagocytosis, and adhesiveness were inhibited by smoke and ethacrynic acid, but not by ouabain. Acrolein, a component of smoke, inhibited phagocytosis, adhesiveness, and calcium-dependent adenosine triphosphatase activity, indicating that another component of smoke must be effective at inhibiting magnesium-dependent adenosine triphosphatase activity. Sodium-potassium-dependent adenosine triphosphatase activity was inhibited by ouabain and ethacrynic acid, but not by smoke or acrolein. Finally, sulfhydryl reagents at least partially protected the macrophages against the inhibitory actions of each of the agents. The results are in accord with recently obtained experimental evidence that calcium-dependent adenosine triphosphatase and, perhaps, magnesium-dependent adenosine triphosphatase play a role in phagocytosis. The data also suggest that smoke components affect a number of macrophage activities, including adhesion and phagocytosis, by altering the cell's contractile apparatus.
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PMID:Correlated effects of cigarette smoke components on alveolar macrophage adenosine triphosphatase activity and phagocytosis. 16 34

The hydrolysis of disodium p-nitrophenyl phosphate at pH 9.0 by slices of formaldehydee-fixed rat renal cortex was investigated by colorimetric estimation of the nitrophenol liberated. It was found that three types of activity could be identified on the basis of their responses to inhibitors and cations: (a) alkaline phosphatase sensitive to inhibition by L-tetramisole; (b) potassium-dependent phosphatase, probably identifiable with the phosphatase component of sodium-potassium-dependent transport adenosine triphosphatase (?Na-K-ATPase); and (c) alkaline phosphatase insensitive to L-tetramisole. It was found that in the presence of strontium ions, as used in Na-K-ATPase cytochemistry, the activities of the second and third types of enzyme were approximately equal. The implications of these findings for the cytochemical demonstration of Na-K-ATPase are discussed.
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PMID:The significance of inhibitor-resistant alkaline phosphatase in the cytochemical demonstration of transport adenosine triphosphatase. 16 3

Enzyme distribution profiles of clarified bovine mammary homogenates separated by equilibrium centrifugation on linear sucrose gradients suggested that several of the commonly utilized marker enzymes for rat liver are also valid markers for mammary cellular components. These marker enzymes include: Succinate dehydrogenase (mitochondria), nicotinamide adenine dinucleotide phosphate cytochrome c reductase and, to a lesser extent, retenone insensitive nicotinamide adenine dinucleotide cytochrome c reductase (endoplasmic reticulum), galactosyl transferase (Golgi apparatus), 5'-nucleotidase (plasma membranes), uric acid oxidase (microbodies), and acid phosphatase (lysosomes). Rotenone sensitive nicotinamide adenine dinucleotide cytochrome c reductase and sodium, potassium, magnesium-stimulated adenosine triphosphatase were widely distributed among subcellular fractions and are not valid marker enzymes. The boyant densities determined for the above fractions should aid in design of methods to obtain enriched sources of these components for analysis.
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PMID:Membranes of mammary gland. XI. Marker enzyme distribution profiles for membranous components from bovine mammary gland. 17 Dec 90

A microsomal fraction rich in Na+, K+-ATPase (sodium-plus-potassium ion-dependent adenosine triphosphatase) and the corresponding K+-dependent p-nitrophenyl phosphatase from the rectal salt gland of the spiny dogfish was solubilized by treatment with deoxycholate at high ionic strength. On gel filtration through Sepharose 6B, the ATPase apoenzyme could be separated, in apparently soluble form, from the tissue-fraction phospholipids and was almost free of enzymic activity (2% of the p-nitrophenyl phosphatase activity and 0.2% of the ATPase activity being recovered). On mixing the apoenzyme with an activator consisting of cooked ox brain, a large proportion of the original enzymic activity was obtained. Specific activities of the re-activated enzyme were somewhat higher than in the material before gel filtration: values of 1300-1450 mumol and 250-290 mumol/h per mg of protein were obtained for the hydrolysis of ATP and of p-nitrophenyl phosphate respectively. The activity was inhibitible by ouabain.
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PMID:The reversible delipidation of a solubilized sodium-plus-potassium ion-dependent adenosine triphosphatase from the salt gland of the spiny dogfish. 17 57

Potassium-stimulated p-nitrophenylphosphatase (K+-pNPPase) activity was investigated in rat somatosensory cortex where 64-88% of enzymatic activity survived 5-10 min of fixation with 3% formaldehyde in 0.1 M cacodylate buffer, pH 7.4. Potassium-stimulated activity was inhibited by 1-10 mM ouabain. Levamisole (1.7 mM) inhibited brain alkaline phosphatase activity, facilitating the detection of K+-pNPPase activity. Strontium (10-20 mM) inhibited enzymatic activity by 38-75%. In parallel histochemical studies reaction product was found in strata, with cortical layers 2, 3, 4 and the outer portion of 5 containing the heaviest deposits. Highly reactive, vertically oriented, large diameter fibers were seen as groups between the outer portion of layer 5 and the pail surface. These fibers apparently arborize in the superficial layers. Smaller fibers were also positive and were oriented in various planes. The highest density of smaller, positive fibers occurred in layers 2 through 5. All positive fibers appeared to be axons or dendrites. Reaction product was not heavily concentrated in neuron perikarya or in glial elements. Sections did not contain reaction product when incubated in media lacking K+ or containing ouabain. The convergence of data from parallel histochemical and biochemical approaches supports the conclusion that the reactivity localized in the cerebral cortex represented the site of K+-pNPPase, a known component of the Na+,K+-adenosine triphosphatase complex. Neuronal processes demonstrated the highest enzymatic activity and may be most important in the active transport of Na+ and K+ in somatosensory cortex.
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PMID:Histochemical localization of potassium-stimulated P-nitrophenylphosphatase activity in the somatosensory cortex of the rat. 18 89

Cardiotoxin isolated from Naja mossambica mossambica selectively deactivates the sodium-potassium activated adenosine triphosphatase of axonal membranes. Tetrodotoxin binding and acetylcholinesterase activities are unaffected by cardiotoxin treatment. The details of association of cardiotoxin with the axonal membrane were studied by following the deactivation of the sodium-potassium activated adenosine triphosphatase and by direct binding measurements with a tritiated derivative of the native cardiotoxin. The maximal binding capacity of the membrane is 42-50 nmol of cardiotoxin/mg of membrane protein. The high amount of binding suggests association of the toxin with the lipid phase of the membrane. It has been shown that cardiotoxin first associates rapidly and reversibly to membrane lipids, then, in a second step, it induces a rearrangement of the membrane structure which produces and irreversible deactivation of the sodium-potassium activated adenosine triphosphatase. Solubilization of the membrane-bound ATPase with Lubrol WX gives an active enzyme species that is resistant to cardiotoxin-induced deactivation. Cardiotoxin binding to the membrane is prevented by high concentrations of Ca 2+ and dibucaine. Although cardiotoxins and neurotoxins of cobra venom have large sequence homologies, their mode of action on membranes is very different. The cardiotoxin seems to bind to the lipid phase of the axonal membrane and inhibits the sodium-potassium activated adenosine triphosphatase, whereas the neurotoxin associates with a protein receptor in the post-synaptic membrane and blocks acetylcholine transmission.
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PMID:Molecular mechanism of cardiotoxin action on axonal membranes. 18 4

Degeneration of testis has been observed after administration of Iodine-125 in potassiumperchlorate treated rats. Histological damage is associated with loss of DNA, RNA, acid phosphatase, total adenosine triphosphatase (ATPase) and Na/K dependent ATPase. Iodine-125 induced atrophic testis shows higher content of sodium and lower levels of potassium as compared to control testis. Damage of testis by Iodine-125 has been compared with atrophied testis, following gamma irradiation earlier reported. Auger effect due to Iodine-125 decay and transmutation at the sites of nuclei and plasma membrane of germinal cells seems to be the possible explanation for testicular damage caused by Iodine-125.
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PMID:Biological damage in testis by iodine-125 in partially blocked thyroid of rats. 19 64

Activity of enzymes catalizing bioenergetic processes of substance transport through cell membranes, adenosine triphosphatase and para-nitrophenyl phosphates, activity of certain enzymes of carbohydrate metabolism, lactate dehydrogenase and glucose-6-phosphate dehydrogenase, as well as to 5'-nucleotidase taking part in nucleic metabolism were determined in the pancreas of thyreoidectomized rats. Simultaneously the content of lactic acid, phosphorus, potassium and sodium, which immediately related to activation of the mentioned enzymes, was determined in the pancreas. In thyroidectomized rats the activity of Mg2+, Na+, K+-ATPase, Na+, K+-ATPase and lactate dehydrogenase in the pancreas increases, that of glucose-6-phosphate dehydrogenase, para-nitrophenylphosphatase and 5-nucleotidase decreases, the content of lactic acid, potassium, sodium and phosphorus increases.
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PMID:[Adenosine triphosphatase, lactate dehydrogenase and glucose-6-phosphate dehydrogenase activity of pancreas of thyroidectomized rats]. 20 6

In order to study the action of the divalent cation which is essential for phosphorylation of sodium- and potassium-transport adenosine triphosphatase, magnesium ion, the normal ligand, was replaced with calcium ion, which had properties diffeerent from those of Mg2+, Mn2+, Fe2+, Co2+, Ni2+, or Zn2+. Phosphorylation of the enzyme from ATP at pH 7.4 in the presence of Na+ and Ca2+ yielded a Ca.phosphoenzyme (60% of the maximal level) with a normal rate of dephosphorylation following a chase with unlabeled Ca.ATP (PK = 0.092S-1 at 0 degrees C). In contrast, after a chase by a chelator, namely ethylenediaminetetraacetic acid, 1,2-cyclohexylenedinitrilotetraacetic acid, or ethylene glycol bis-(beta-aminoethyl ether)N,N'-tetraacetic acid, dephosphorylation slowed within 5 s and half of the initial phosphoenzyme remained with a stability about 5-fold greater than normal. Three states of the phosphoenzyme were distinguished according to their relative sensitivity to ADP or to K+ added during a chase. Normally prepared Mg.phosphoenzyme was sensitive to K+ but not to ADP; Ca.phosphoenzyme was sensitive either to ADP or to K+; and the stabilized phosphoenzyme prepared from Ca.phosphoenzyme by addition of a chelator was sensitive neither to ADP nor to K+ nor to both together. Addition of Ca2+ to the stabilized phosphoenzyme restored the reactivity to that of Ca.phosphoenzyme. Addition of Mg2+ to the stabilized phosphoenzyme changed the reactivity to that of Mg.phosphoenzyme. Therefore, this unreactive, stabilized state of the phosphoenzyme appeared to be a divalent cation-free phosphoenzyme. With respect to sensitivity to ouabain, Ca.phosphoenzyme was as sensitive as Mg.phosphoenzyme but calcium-free phosphoenzyme was much less sensitive. It was concluded that the divalent cation required for phosphorylation normally remains tightly bound to the phosphoenzyme and is required for normal reactivity. Calcium ion was almost unique in dissociating relatively easily from the phosphoenzyme. Strontium ion appeared to act similarly to Ca2+.
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PMID:Binding of divalent cation to phosphoenzyme of sodium- and potassium-transport adenosine triphosphatase. 21 Nov 32

Dopa-decarboxylase, acetylcholinesterase, sodium plus potassium stimulated adenosine triphosphatase (Na+ + K+-ATPase), and membrane-bound protein kinase were compared in the erythrocytes of patients with Huntington's disease and normal controls. All these enzymes also exist in the basal ganglia. The Na+ +K+-ATPase level was elevated (p less than 0.05) in Huntington's disease, while no significant changes were observed in the other enzymes. This finding is consistent with the concept that Huntington's disease is associated with a general membrane abnormality.
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PMID:Increased sodium plus potassium adenosine triphosphatase activity in erythrocyte membranes in Huntington's disease. 21 30


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