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)

Tissue sections of lymph nodes, appendices and tonsils, together with smears of immunologically separated peripheral lymphoid cells from a B-CLL and lymphomatous cells from an immunocytoma were submitted to combined enzyme cytochemical investigations with acid alpha-naphthyl acetate esterase (ANAE), beta-glucuronidase (B-G), acid phosphatase (AcPh), adenosine triphosphatase (ATPase), a,d 5'nucleotidase (5'N). T-cells were Acph+, ATPase- and 5'N-. The vast majority of T- and B-cells displayed ANAE and B-G activities with two distinct staining patterns (T-like and B-like pattern). A high proportion of lymphoid cells in the germinal centre (G.C.) and the vast majority of lymphoid cells in the mantle-zone (M.Z.) were shown to belong to B-cell system because of the expression of ATPase and 5'N in their membranes. Some lymphoid cells positive for ANAE and B-G with a B-like pattern and for AcPh were recognizable in the G.C. In the M.Z. only a few lymphoid cells being ANAE+, with a T-like pattern, and AcPh+ were shown to belong to the T-cell system. In contrast, in this zone a high proportion of small lymphoid cells (64% +/- 10%) showed ANAE activity, mostly with B-like pattern. Therefore, these findings indicate that in the M.Z. a high proportion of B-cells ATPase+ and 5'N+ also display ANAE activity. By comparison of the results obtained from lymphoid tissue sections, B-CLL and immunocytoma cell suspensions and normal circulating lymphocytes we can conclude that B-ANAE-positive cells of the M.Z. do not usually appear in the peripheral blood. They circulate in large numbers only in some pathological conditions (like our reported B-CLL). Therefore, B-ANAE-positive lymphoid cells of the mantle, with a B-like staining pattern, include a wide range of subsets which exclude large lymphoid cells and plasma cells.
Virchows Arch B Cell Pathol Incl Mol Pathol 1982
PMID:Histochemical study on human germinal centre, mantle-zone and extra-follicular area lymphoid cell subpopulations. Immunological and cytochemical correlations with lymphomatous cells, peripheral normal and leukemic lymphocytes. 613 70

Pyrophosphate, p-nitrophenyl phosphate and a variety of pyrimidine and purine nucleotides are hydrolyzed by the solubilized membrane-bound enzymes of the brush border plasma membrane of Hymenolepis diminuta. The pH optima (or ranges) for hydrolysis of substrates are 8.0 (pyrophosphate), 8.8 (p-nitrophenyl phosphate), 8.4-8.9 (nucleoside monophosphates), and 7.1-8.1 (nucleoside triphosphates); all substrates, with the exception of nucleoside triphosphates, have a higher affinity for the solubilized enzyme at pH 7.4 than at their optimal pH for hydrolysis. ATP is degraded completely by the enzyme preparation to adenosine and inorganic phosphate, but since neither ADP nor ATP accumulate in the incubation medium it is not known whether ATP hydrolysis involves the sequential hydrolysis of terminal phosphate groups. Isoelectric focusing and various chromatographic procedures (gel permeation, ion-exchange and hydrophobic interaction chromatography) fail to separate the alkaline phosphatase, phosphodiesterase, 5'-nucleotidase, adenosine triphosphatase and ribonuclease activities associated with the solubilized membrane preparation. Additionally, inhibitor studies indicate that only a single enzyme with low substrate specificity is involved in the hydrolysis of nucleotides, p-nitrophenyl phosphate, pyrophosphate and hexose phosphate esters. Purines and pyrimidines and their nucleosides interact with the active site, and in some instances activity of the enzyme is stimulated by an unknown mechanism.
Mol Biochem Parasitol 1983 May
PMID:Nucleotide hydrolysis by solubilized membrane-bound enzymes of the brush border plasma membrane of Hymenolepis diminuta. 613 88

The reaction of Trypanosoma cruzi Mg2+-stimulated adenosine triphosphatase (ATPase, coupling factor 1, or F1) with phenylglyoxal, a dicarbonylic compound, resulted in a rapid loss of its enzymatic activity. The inactivation showed pseudo-first-order kinetics with both membrane-bound and soluble F1-ATPase, the rate of the enzyme inactivation being faster in bicarbonate buffer (pH 7.9) than in borate buffer (pH 8.0). The log (pseudo-first-order rate constant) vs. log(phenylglyoxal concentration) plots obtained with the membrane-bound and soluble F1-ATPase in bicarbonate buffer, and also with F1 in borate buffer, had slopes of near 1.0 while the plot for the membrane-bound ATPase in borate buffer had a slope of 1.6. Second-order rate constants (in mM-1 X min-1) were 55 (for both ATPase preparations in bicarbonate buffer) and 34 (for the membrane-bound ATPase in borate buffer). When the reaction was performed in the presence of ATP, the rate of inactivation was significantly decreased. It is concluded that, as in the mammalian F1-ATPase, arginyl residues play an essential role in T. cruzi mitochondrial ATPase, probably at the hydrolytic site.
Mol Biochem Parasitol 1982 Jun
PMID:Phenylglyoxal inactivation of the mitochondrial adenosine triphosphatase from Trypanosoma cruzi. 621 57

Time- and dose-dependent changes in intracellular enzyme activities in kidney and bone from rats injected with calcitonin have been assessed by quantitative cytochemistry. The doses of salmon calcitonin given were similar to those suggested in the Pharmacopoeial rat hypocalcaemia bioassay (1-50 mIU/50 g body weight). The highest doses produced 30% inhibition of alkaline phosphatase activity, maximal within 20 min after injection, in cells of renal proximal tubules and a stimulation of calcium-dependent adenosine triphosphatase activity in kidney cortical and outer medullary cells. Alkaline phosphatase activity in the periosteal bone cells was markedly inhibited at the lowest doses. When doses of human and porcine calcitonins were given which would be equipotent with that of salmon calcitonin in the rat hypocalcaemia bioassay, the effect of the non-mammalian peptide on renal alkaline phosphatase activity was relatively greater than that of the mammalian peptides. Oxidized human calcitonin did not inhibit renal alkaline phosphatase activity even when an amount equivalent to 10 times the highest dose of the unmodified peptide was injected.
Mol Cell Endocrinol 1983 Dec
PMID:Quantitative cytochemical responses to exogenously administered calcitonins in rat kidney and bone cells. 622 49

Effects of some organic compounds of different hydrophobicity on the structure and ion specificity of the sodium-potassium adenosine triphosphatase (Na,K-ATPase) membrane preparation were studied. Inhibition abilities of these compounds correlate well with their lipophilic properties. High hydrophobic compounds change mainly the enzyme activation by potassium ions and the spin label mobilities in hydrophobic regions of the membrane preparation. Polar species, in contrast, influence the enzyme activation by sodium ions and the surface polar properties of the membrane preparation. It is supposed, that the Na,K-ATPase activations by potassium and sodium ions are correspondingly related to hydrophobic regions of the lipoprotein enzyme complex and to the polar regions stabilized by hydrogen bonds.
Mol Biol (Mosk)
PMID:[Physico-chemical principles for discrimination of sodium and potassium ions by membrane Na pumps. I. Effect of organic compounds on the ionic specificity of Na, K-ATPase]. 625 15

The mitochondrial adenosine triphosphatase of the kinetoplastid protozoon, Crithidia fasciculata, is inhibited by oligomycin, venturicidin, triethyltin sulphate, N,N'-dicyclohexylcarbodiimide, leucinostatin, Dio-9 and quercetin, but not spegazzinine or by compounds which interact with the beta-subunit of mitochondrial F1-ATPase (efrapeptin, aurovertin, citreoviridin or 4-chloro-7-nitrobenzofurazan). These results suggest that the F1 portion of the crithidial enzyme has an unusual type of beta-subunit. Further evidence for the atypical nature of this enzyme is provided by the observation that F1-inhibitor proteins from Acanthamoeba castellanii or bovine heart mitochondria do not inhibit the C. fasciculata enzyme activity.
Mol Biochem Parasitol 1981 May
PMID:Effects of inhibitors on mitochondrial adenosine triphosphatase of Crithidia fasciculata: an unusual pattern of specificities. 645 44

During growth and maturation of the tapeworm, Hymenolepis diminuta, significant decreases occur in the brush border membrane-bound alkaline phosphatase, phosphodiesterase, 5'-nucleotidase, adenosine triphosphatase and ribonuclease activities. These decreases are accompanied by qualitative and quantitative changes in the polypeptide profiles of the brush border membrane fraction. Gradients of enzymatic activities and polypeptide profiles are also demonstrable when mature tapeworms are cut into pieces and the brush border membrane of each piece analyzed individually. In fully developed tapeworms the enzymatic activities and polypeptide profiles of membrane preparations reflect mainly the contributions of the more mature proglottids; these proglottids constitute most of the tapeworm biomass. The most anterior sections of these fully developed worms are biochemically similar to young, developing worms.
Mol Biochem Parasitol 1983 Aug
PMID:Alterations in brush border membrane proteins and membrane-bound enzymes of the tapeworm, Hymenolepis diminuta, during development in the definitive host. 663 65

Among the proto-oncogenes examined by northern blot analysis, c-myc, c-Ha-ras, c-fos, and c-raf-1 have been reported to be activated in rat liver cell carcinomas. However, there are relatively few reports on protooncogene expression in altered hepatic foci (AHF) early during hepatocarcinogenesis in the rat. In this study, diethylnitrosamine (DEN) at doses ranging from 10 to 200 mg/kg was used to initiate and phenobarbital (0.05%) to promote AHF in rats. AHF were detected by the presence of the marker enzymes glutathione s-transferase, placental form (GST-P); gamma-glutamyltranspeptidase (GGT); glucose-6-phosphatase (G6Pase); and canalicular adenosine triphosphatase (ATPase). Proto-oncogene expression in individual AHF was investigated by in situ hybridization (ISH). ISH for the mRNAs of c-Ha-ras, c-fos, and c-raf-1 revealed little or no expression in AHF. However, the levels of c-myc mRNA were increased in about 10% of the AHF initiated by the highest dose of DEN (200 mg/kg). Thus, altered expression of proto-oncogenes was not seen in AHF initiated by nonnecrogenic doses of DEN and promoted by phenobarbital. However, at the necrogenic dose of 200 mg/kg DEN, c-myc expression was found mostly in AHF in which abnormal expression of GST-P, GGT, G6Pase, and ATPase was also present, indicating that c-myc expression is correlated with phenotypically greater complexity of the AHF, a characteristic of malignant hepatic neoplasms in the rat.
Mol Carcinog 1995 Nov
PMID:Expression of c-myc in altered hepatic foci induced in rats by various single doses of diethylnitrosamine and promotion by 0.05% phenobarbital. 757 7

The effect of various potassium concentrations (ranging from 1.4 mM to 30 mM K+) in modified Tyrode's medium on the culture of mouse zygotes obtained after in vitro fertilization to the blastocyst stage was examined. A clear dose-dependent negative effect of increasing K+ concentrations on the preimplantation embryonic development in vitro was found. We have previously shown that significantly more two-cell embryos reach the blastocyst stage when cultured during the second day postinsemination in medium supplemented with taurine. Because taurine, an amino acid that abounds in the reproductive tract, has been reported to inhibit the enzyme Na(+)-K(+)-adenosine triphosphatase (Na(+)-K(+)-ATPase), we used two other conditions known to inhibit the Na(+)-K(+)-ATPase to study their effect on mouse embryo development. Culturing embryos during a short period (the second day postinsemination) in low extracellular K+ concentrations (1.4 mM) or in medium supplemented with ouabain (50 microM) showed positive effects similar to those of culturing in medium with taurine (10 mM). This beneficial effect of ouabain was found in various K+ concentrations tested, including the high concentrations present in the oviduct. Although the effects of low K+ and taurine can possibly be ascribed to their other cellular effects, the effect of ouabain shows that inhibition of the Na(+)-K(+)-ATPase during the two-cell stage in the mouse is beneficial for further embryonic development to the blastocyst stage.
Mol Reprod Dev 1993 Nov
PMID:Modulation of embryonic Na(+)-K(+)-ATPase activity and mouse preimplantation development in vitro in media containing high concentrations of potassium. 828 13

Two experiments were conducted to determine the overall influence of porcine somatotropin (pST) administration on the specific activity of visceral tissue ATPases. Pigs were fed a corn-soybean meal-skim milk-based diet approximately 85% of ad libitum, such that for each experiment, control and pST-treated pigs consumed similar amounts of feed. As observed for pigs chronically treated with pST, enhanced growth of visceral tissues was evident in pigs treated for 6 and 14 days (d) with pST. The specific activity of detergent-activated Na(+)-K(+)-ATPase (ouabain-sensitive adenosine triphosphatase activity) was determined in fresh tissue homogenates prepared from liver, heart, kidney and duodenum. Treatment with pST was associated with a 19% increase in Na(+)-K(+)-ATPase-specific activity in the liver; specific activity of Mg(2+)-ATPase was not influenced by pST. Whole liver Na(+)-K(+)-ATPase and Mg(2+)-ATPase activities were 35% and 25% greater, respectively, in somatotropin-treated pigs. The specific activities of Na(+)-K(+)-ATPase in heart, kidney and duodenum were similar for controls and pigs treated for 14 d with pST. The specific activities of high- and low-affinity Ca(2+)-ATPase in kidney medulla were 20 and 26% lower, respectively, in pigs treated for 14 d with pST compared with controls. In contrast, Ca(2+)-ATPases in other tissues, including kidney cortex, were not influenced by pST treatment. These data indicate that some of the observed increase in energy expenditure associated with pST treatment may be attributable to increased organ size as well as to enhanced hepatic Na+ and K+ flux. While Na(+)-K(+)-ATPase activity is specifically enhanced in the liver, pST does not appear to be a general Na(+)-K(+)-ATPase activator in all tissues and may be associated with depressed activity of Ca(2+)-ATPases in the kidney.
Comp Biochem Physiol B Biochem Mol Biol 1996 Sep
PMID:Influences of somatotropin on Na(+)-K(+)-ATPase, Mg(2+)-ATPase and Ca(2+)-ATPases of Porcine visceral tissues. 889 28


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