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)

The following enzymes have been studied (subcellular fractions are shown between parentheses): NAG and beta-glucuronidase (lysosomes); SDH (mitochondrial); glucose-6-phosphatase (endoplasmic reticulum); 5'-nucleotidase and (Na+, K+)Mg2+ ATPase (plasma membranes). Alterations on their activities were observed after subcutaneous injection of sex hormones, compared with controls. NAG activity from liver was always significantly decreased in lysosomal and microsomal fractions after the hormonal treatment. In the same conditions, NAG from brain was always increased. beta-Glucuronidase behaves like NAG in brain; in liver it was not modified by testosterone and it was slightly increased in lysosomal fraction after oestradiol treatment. SDH activity was not modified in mitochondrial fractions from liver, but this activity was always significantly increased in brain. Glucose-6-phosphatase activity was always significantly decreased in microsomal fractions from liver. It was increased in brain after oestradiol and testosterone injection, but medroxyprogesterone treatment caused a decreased activity. 5'-Nucleotidase and (Na+, K+)Mg2+ ATPase from brain were significantly increased in microsomal fractions by oestradiol and testosterone. Medroxyprogesterone, however, caused an increase in ATPase, but did not affect 5'-nucleotidase. Both activities in liver were decreased by oestradiol and increased by testosterone, but medroxyprogesterone caused (Na+, K+)Mg2+ ATPase to rise and 5'-nucleotidase to fall.
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PMID:Effects of oestradiol, testosterone and medroxyprogesterone on subcellular fraction marker enzyme activities from rat liver and brain. 298 29

The effect of subcutaneous injection of hydrocortisone and corticosterone on the activity values of some subcellular fractions marker enzymes from rat liver and brain was investigated and compared with controls (without treatment with hormones). The following enzymes were studied (subcellular fraction are shown between parentheses): N-acetyl-beta-D-glucosaminidase and beta-glucuronidase (lysosomes); succinate dehydrogenase = SDH (mitochondria); glucose-6-phosphatase (endoplasmic reticulum); 5'-nucleotidase and Na+-K+-Mg2+ ATPase (plasma membrane). The specific activity of lysosomal enzymes from liver showed no change when rats were injected either with hydrocortisone or corticosterone. The same enzymes from brain showed significant increases in their activities with both hydrocortisone or corticosterone except beta-glucuronidase; this enzyme gave activity values remaining between the control levels, after treatment with corticosterone. The activity of mitochondrial SDH was increased after corticosterone injection either in liver or brain. After hydrocortisone injection, its activity rises significantly in brain (72%), but it falls in liver compared to the control values. Glucose-6-phosphatase behaves similarly in brain or liver fractions; its activity increases always after corticosterone treatment and decreases by hydrocortisone. The plasma membrane marker enzymes did not change practically in brain fractions, excepted Na+-K+-Mg2+ ATPase which tends to rise its activity after hydrocortisone injection. In liver fractions, both 5'-nucleotidase and Na+-K+-Mg2+ ATPase activities increase either by corticosterone or hydrocortisone treatment, except 5'-nucleotidase which specific activity decreases in liver after hydrocortisone treatment.
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PMID:Alterations in the activities of subcellular fractions marker enzymes in rat liver and brain by hydrocortisone and corticosterone treatment. 298 17

Pinocytosis was induced in rat kidney by exposure to horseradish peroxidase (HRP). Pinocytic vesicle preparations were enriched after homogenization of kidney cortex by differential centrifugation and free-flow electrophoresis with HRP as an exogenous marker. Vesicles were identified by enzymatic analysis and by electron microscopy, including specific staining procedures. Typical brush-border enzymes such as alkaline phosphatase, aminopeptidase, 5'-nucleotidase, lysosomal acid phosphatase, and mitochondrial succinic dehydrogenase were reduced in the vesicular fraction, compared to the kidney cortex homogenate. Glucose-6-phosphatase and Na(+)-K(+)-ATPase were only slightly increased in the fraction. These results indicate that preparations of pinocytic vesicles from rat kidney cortex can be enriched. They have biochemical characteristics that differ from those of the cell organelles and membranes previously purified from renal tissue.
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PMID:Analysis of the pinocytic process in rat kidney. I. Isolation of pinocytic vesicles from rat kidney cortex. 437 80

Cytoplasmic changes were investigated in livers of rats at various intervals up to 50 weeks during primary induction of hepatoma by thioacetamide feeding.Microsomal Glucose-6-phosphatase and ATPase activities were shown to decrease progressively with increased period of thioacetamide feeding the fall in activities being more pronounced during the first 15 weeks.Hormonal induction of tryptophan pyrrolase and tyrosine transaminase activities was shown to undergo a significant decrease of 65% and 55% respectively at the end of 50 weeks feeding.The substrate induced tryptophan pyrrolase activity was decreased to 50% during the 50 weeks period whereas the substrate induced tyrosine transaminase activity gradually increased to 200%. The latter is attributable to differences in the optimal induction dose of tyrosine in normal and carcinogen fed rats.The m-RNA template lifetime for tryptophan pyrrolase was shown to be exceeding 24 hours in normal rats as against that of 13 hours in rats fed with carcinogen for 30 weeks. On the other hand the m-RNA template lifetime for tyrosine transaminase was 3 hours in control rats while it was 7 hours in the carcinogen fed rats.The observed changes were shown to occur long before the onset of malignant transformation.The alterations in terms of decreased Glucose-6-phosphatase and substrate induced tryptophan pyrrolase activities were shown to be reversible when the carcinogen was withdrawn from the diet after 30 weeks of feeding.The significance of these observations is discussed in relation to damage to endoplasmic reticulum during hepatocarcinogenesis.
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PMID:Cytoplasmic changes during thioacetamide induced hepatocarcinogenesis in rats. 439 24

The histochemical characteristics of spontaneous hepatocellular neoplasms in mice of both sexes were examined and compared with those of hepatocellular neoplasms induced in female mice by administration of polycyclic aromatic hydrocarbon carcinogens as initiators with or without subsequent phenobarbitone treatment. Controls treated with phenobarbitone alone was also induced. Spontaneous neoplasms in the livers of mice rendered siderotic by subcutaneous iron injection were deficient in cellular accumulation of stainable iron. Glucose-6-phosphatase activity was deficient in the majority of spontaneous and induced neoplasms. ATPase activity was increase in about half of spontaneous and carcinogen-induced neoplasms but all induced neoplasms in mice treated with phenobarbitone showed deficient activity. Gamma-glutamyltransferase activity was present in very few of the spontaneous neoplasms or in the neoplasms induced in the absence of phenobarbitone administration. However, all induced neoplasms in the mice receiving phenobarbitone showed some degree of gamma-glutamyltransferase activity together with deficient glucose-6-phosphatase and ATPase activities. It is concluded that the histochemical characteristics of spontaneous or induced mouse hepatocellular neoplasms are variable and may be influenced by the inducing factors.
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PMID:Histochemical characteristics of spontaneous and chemically induced hepatocellular neoplasms in mice and the development of neoplasms with gamma-glutamyl transpeptidase activity during phenobarbital exposure. 611 14

Histochemical techniques described by McManus (1960) have been applied in the fishes, Notopterus notopterus and Colisa fasciatus, for the study of Glucose-60phosphatase and adenosine triphosphatase in the four stages of gonads in different seasons. It has been observed that the activity of adenosine triphosphatase is more intense in comparison to the activity of Glucose-6-phosphatase in all the stages i.e. I (immature), II (maturing), III (mature) and IV (spent) of the gonads in both the fishes. The general tendency of the adenosine triphosphatase and Glucose-6-phosphatase distribution in the gonads are much more remarkable in stage II in comparison to stage I, III and IV. The stage I seems to be the stage of synthesis of these enzymes. In stage III and IV, these enzymes show the tendency of declination with the time period. The possible role of these enzymes seems to be the transport of glucose across the cell membrane involving phosphorylation and dephosphorylation which depend on the different stages of gonad maturation.
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PMID:Histo-chemical mapping of phosphomonoesterases in the gonads of Notopterus notopterus and Colisa fasciatus during different seasons. Part II. Adenosine triphosphatase and glucose-6-phosphatase. 625 10

The livers of male inbred F344 rats fed Wy-14,643 [4-chloro-6-(2,3-xylidino)-2-pyrimidinylthio] acetic acid (CAS: 50892-23-4) in the diet at a concentration of 0.1% (wt/wt) were examined sequentially at 5, 10, 17, 21, 26, 30, 35, 40, 52, 60, and 70 weeks. At 5 weeks the livers were markedly enlarged and histologically showed markedly enlarged hepatocytes with prominent nucleoli. At 21 weeks altered acidophilic areas were seen in 2 of 3 animals that were killed. Between 26 and 52 weeks neoplastic nodules were noted of 1-8 mm containing cells with morphologic features similar to those observed in altered areas. Hepatocellular carcinomas (HCC) were observed in 1 animal killed at 30 weeks and in all the animals sacrificed at 60 weeks and later. [3H]thymidine nuclear labeling studies showed marked proliferative activity of cells in altered areas, neoplastic nodules, and HCC. Altered areas, neoplastic nodules, and HCC were consistently negative for gamma-glutamyltransferase and showed decreased ATPase activity. Glucose-6-phosphatase (Glc-6-Pase) activity was decreased in altered areas and neoplastic nodules. However, some of the HCC showed a strong positive reaction for Glc-6-Pase.
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PMID:Sequential histologic study of rat liver during peroxisome proliferator [4-chloro-6-(2,3-xylidino)-2-pyrimidinylthio]-acetic acid (Wy-14,643)-induced carcinogenesis. 659 91

A fraction containing plasma membrane-enriched vesicles has been prepared from Tritrichomonas foetus. Cells were ruptured using a Potter type homogenizer, under well controlled conditions, and membranes were isolated by differential centrifugation and in discontinuous sucrose gradient. This fraction was enriched 8 and 10-fold in the plasma membrane marker enzymes 5'-nucleotidase and (Na+ + K+)-dependent, ouabain-sensitive ATPase, respectively. Determination of Glucose-6-phosphatase and NADPH cytochrome c reductase activities in this fraction, indicates a minimal contamination with endoplasmic reticulum membranes. Analysis by Sodium Dodecyl Sulfate-Polyacrylamide (SDS-PAGE) gradient gel showed that the plasma membrane fraction contains several proteins with major bands corresponding to apparent molecular weights of 48, 45, 39, 37, 32, 30, 27, 23, 20, 19, 17, and 15 kDa.
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PMID:Isolation and biochemical characterization of the plasma membrane of Tritrichomonas foetus. 865 56

Glucose-6-phosphatase (G6Pase) is a multiple protein complex in the endoplasmic reticulum (ER) that includes a mechanism (known as T3) for glucose exit from the ER to the cytosol. The molecular identity of T3 is not known. T3 has been shown to be functional in the absence of GLUT2, indicating that it is not GLUT2. Here we found a 55-kDa protein in high-density microsomal fraction (HDM) of rat hepatocytes that is recognized by polyclonal GLUT2 antibody raised against the GLUT2 C-terminal 14-amino-acid-sequence peptide. HDM contained calnexin but no integrin-beta1 or Na/K ATPase in Western blotting. Significant GLUT2 immunoreactivity was colocalized with colligin, an ER marker, in confocal microscopy. Furthermore, the 55-kDa protein in HDM was labeled with a covalently reactive, impermeable glucose transporter substrate, 1,3-bis-(3-deoxy-D-glucopyranose-3-yloxy)-2-propyl 4-benzoyl-benzoate (B3GL) when hepatocyte homogenates, but not intact cells, were labeled. In addition glucose efflux from HDM vesicles was sensitive to B3GL treatment in a dose-dependent manner. Based on these findings, we suggest that T3 may be a novel facilitative glucose transporter that is highly homologous to GLUT2 in the C-terminal sequence, thus cross-reacting with the GLUT2 antibody. The finding will be useful in molecular identification and cloning of T3.
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PMID:The hepatocyte glucose-6-phosphatase subcomponent T3: its relationship to GLUT2. 1210 Oct 13


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