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)

Male Wistar rats were given 50 mug of aflatoxin B1 twice a week for 4 weeks, and thereafter 75 mug twice a week for 10 weeks. Their livers were investigated histologically and histochemically for glycogen, RNA, fat, alkaline and acid phosphatases, adenosine triphosphatase, 5'-nucleotidase, glucose-6-phosphatase, glucose-6-phosphate dehydrogenase, succinic dehydrogenase, and alkaline and acid nucleases. No significant lesions occurred before 15 weeks. During this period, the liver was histochemically unchanged except for a periportal decrease of alkaline phosphatase and adenosine triphosphatase. Scattered hepatocytes with a strong glucose-6-phosphatase activity appeared. These changes represent toxic effects of aflatoxin B1 and are irrelevant to carcinogenesis. From 15 weeks onward, three types of liver cell hyperplastic foci and nodules developed. Histologically, and with respect to glycogen, fat, and RNA content, only two of these types were considered as potential precursors of hepatocarcinomas. However, all types exhibited a decrease or absence of the enzymes studied. Both histological and histochemical changes stressed the complex heterogeneity existing between and within hepatic foci and nodules. From 11 months on, hepatocarcinomas developed. The tumors disclosed similar histochemical changes. This similarity further supports the "precarcinomatous" nature of hyperplastic foci and nodules. It appears that focal changes in surface as well as in cytoplasmic and nuclear enzymes are intimately and very early linked to the carcinogenic process. Whether they are fundamental or only represent an epiphenomenon remains unclear.
Cancer Res 1975 Oct
PMID:Sequential histological and histochemical study of the rat liver during aflatoxin B1-induced carcinogenesis. 16 70

Antisera were produced against an SV40-transformed cell line in the syngeneic AL/N mouse. With a microcytolytic assay, the specificity of antisera produced by various immunization schedules and their ability to lyse numerous SV40-transformed cell lines were determined. Various AL/N mouse cell lines, newly transformed by SV40 and cloned, were found to be lysed by the antisera. When tumors were induced by SV40-transformed cells in the syngeneic mouse and cell lines were reestablished from tumors and such procedures were repeated, the susceptibility to serum-mediated cytolysis of the sublines was the same as that of the original SV40-transformed cell line, in spite of differences in tumorigenicity. Polyoma virus-transformed AL/N cell lines were also lysed while AL/N embryo cells, untransformed by SV40 or by polyoma, were not. SV40-transformed T-antigen-positive BALB/c mouse or hamster cell lines or a T-antigen-positive tissue cultured human cell were also resistant to lysis. A competition type of microassay demonstrated specific inhibition of the serum-mediated cytolysis by all of the SV40 T-antigen-positive cell lines tested. Thus, the lack of lysis of cells did not necessarily indicate the absence of SV40-induced surface antigens. The polyoma-transformed AL/N cell line also inhibited the antisera, but to a lesser extent, suggesting the possibility that SV40 and polyoma virus transformation may result in the appearance of partially common cell surface antigens.
Cancer Res 1976 Jan
PMID:Limitations and utility of a cytolytic assay for measuring simian virus 40-induced cell surface antigens. 17 16

The histochemical reaction for adenosine triphosphatase (ATPase) has previously been used to differentiate myoepithelial from epithelial cells in the breast and to investigate the possible contribution of myoepithelial cells to mammary carcinoma. Discrepancies in published reports prompted this study of ATPase in non-neoplastic breast and infiltrating ductal carcinoma. ATPase was localized mainly on myoepithelial cells of normal breast and was identified with significant frequency on epithelial cells in hyperplastic ducts. Infiltrating ductal carcinomas usually displayed a variable reactivity. In one instance, malignant cells demonstrating mucin production were found to be ATPase-positive. An infiltrating ductal carcinoma of the papillary type with apocrine features was also strongly ATPase-reactive. It is concluded that ATPase is not an exclusive marker of myoepithelial cells and, therefore, data resulting from the use of this enzyme to study the role of the myoepithelium in mammary carcinoma must be interpreted with caution.
Cancer 1976 Aug
PMID:Distribution of adenosine triphosphatase in infiltrating ductal carcinoma and non-neoplastic breast. 18 14

Epstein-Barr virus-associated, complement-fixing antigens have been observed with a complement-mediating immunoreaction and with the peroxidase-labeled anticomplement antibody electron microscopic method. Postive reaction products could be found in the nuclei of P3HR-1 cell lines. At high magnification, it was ascertained that the reaction-positive precipitates were associated with chromatin and were mostly either finely granular or filamentous, which suggests that the antigen was not uniform. It was speculated that the antigen would be analogous to the SV40 T-antigen, since the localization pattern of the positive reaction was similar in both antigens. This new, modified method using complement may also be used for detection of a natural antibody of unknown class or for low-sensitivity systems of antigen-antibody reactions. Thus, this method appears useful for studying various kinds of experimental materials.
Cancer 1976 Nov
PMID:An immunoelectron microscopic analysis of Epstein-Barr virus-associated complement-fixing antigen. 18 78

Activities of a broad spectrum of enzymes were studied histochemically in renal adenocarcinomas induced in young male F344 rats by chronic dietary administration of the carcinogen N(4'-fluoro-4-biphenylyl)acetamide. Enzymes included were: dehydrogenases of glucose-6-phosphate, lactate, succinate, malate, and alpha-glycerophosphate; peroxidase (catalase); glucose-6-phosphatase; alkaline and acid phosphatase; Mg2+ ATPase; 5'-nucleotidase; and aminopeptidase. Levels of enzyme activity were estimated visually and scored from 0 (not detectable) to a maximum of 5 (intense). Comparison of estimated activity for each enzyme was made between small neoplastic nodules (stage III tumors) and large adenocarcinomas (stage IV tumors) and between tumors and portions of normal proximal tubules in parenchyma of kidneys from untreated control rats. The results, which revealed nearly identical levels of activity for most enzymes in both stages III and IV tumors, suggested similar metabolic and biologic behavior of these lesions. However, when data for tumors were compared with data for normal proximal tubules, striking differences were observed consistent with: 1) a marked shift of energy metabolism from oxidative to glycolytic production of ATP, with a corresponding reduction in mitochondrial respiration; and 2) simplification of plasma membrane specializations that were possibly associated with a reduction or loss of transport function. These findings were compared with other histochemical, biochemical, and ultrastructural studies of renal adenocarcinomas in rats and man.
J Natl Cancer Inst 1976 Oct
PMID:Adenocarcinoma of the kidney. II. Enzyme histochemistry of renal adenocarcinomas induced in rats by N-(4'-fluoro-4-biphenylyl)acetamide. 18 77

In this first paper of a series comparing the membranes of normal lymphocyte populations from male outbred Syrian hamsters with those of neoplastic transformants (GD 248) induced by simian virus 40, a method is described for the isolation of representative plasma membrane (PM) fragments from both cell types. Multiple criteria were used to monitor the purity and yield of PM material after cell disruption by nitrogen cavitation and after membrane fractionation by a combination of differential centrifugation and isopyknic ultracentrifugation in dextran density gradients. Lactoperoxidase-catalyzed radioiodination before cell disruption was used as an extrinsic surface marker; Na+,K+-activated ATPase, as well as alkaline phosphatase, was used as intrinsic functional PM markers. The distribution of nuclei, mitochondria, lysosomes, and endoplasmic reticulum (ER) during fractionation was monitored by the measurement of DNA, succinate dehydrogenase and monoamine oxidase, beta-glucuronidase and glucose-6-phosphatase, and NADH:lipoamide oxidoreductase, respectively. According to the three PM markers employed, a 15- to 20-fold purification (over homogenate) and a PM yield of about 65% were obtained for both cell categories, with negligible contamination by DNA, mitochondria, lysosomes, and er. The procedure also allowed recovery of 60% of the mitochondria free of other cell elements.
J Natl Cancer Inst 1976 Nov
PMID:Membranes of normal hamster lymphocytes and lymphoid cells neoplastically transformed by simian virus 40. I. High-yield purification of plasma membrane fragments. 18 92

Six young adult male rhesus monkeys were given diethylnitrosamine ip for 3-5 years. Liver biospies were done monthly. After 6 months, biopsy specimens showed individual hepatocytes and small foci of hepatocytes that were intensely positive for glycogen. During the second and later years, larger foci of such cells developed. In sections stained with hematoxylin and eosin, the glycogen-containing hepatocytes generally appeared unusually clear. Some hepatocytes, however, had eosinophilic or basophilic cytoplasm. Nuclear enlargement and atypic developed, particularly outside the foci. The hepatocytes within most foci were uniform in their histochemical features: glycogen was elevated, glucose-6-phosphatase was decreased, and ATPase activity was present not only along the bile canalicular surface but also along the enire cell membrane. After 3-5 years, neoplastic nodules and hepatocarcinomas developed in 5 of 6 animals. Two nodules and particularly the heptocarcinomas differed from the foci in one of more histochemical parameters. The findings suggested that the glycogen-containing, histochemically altered cells of the foci in one or more histochemical parameters. The findings suggested that the glycogen-containing, histochemically altered cells of the foci may be the first step in the development of neoplasia; further steps toward malignancy appeared to be frequently associated with additional alterations, such as loss of sinusoidal ATPase and re-formation of glucose-6-phosphatase.
J Natl Cancer Inst 1976 Dec
PMID:Sequential hepatic histologic and histochemical changes produced by diethylnitrosamine in the rhesus monkey. 18 98

Different adenosine triphosphatase (ATPase) activities were detected at an ultrastructural level in order to differentiate epithelial and myoepithelial cells in normal and neoplastic mouse mammary tissues. Mg2+ dependent and Na+-K+-dependent ATPase activities were studied in: BALB/c mouse mammary gland; a BALB/c carcinoma from a transplantable D2 hyperplastic nodule; a stable cell line, MCF-8, derived from the BALB/c carcinoma; and a BALB/c scirrhous-like carcinoma induced by MCF-8 cell inoculation. Mg2+-dependent ATPase was detected in the plasma membranes of the normal mouse mammary epithelial cells, the epithelial component of the BALB/c carcinoma, the MCF-8 cells in culture, and the atypical epithelial component of the scirrhous-like carcinoma. Na+-K+-dependent and Mg2+-dependent ATPase were localized in the plasma membranes of the myoepithelial cells of the normal mammary gland and the BALB/c carcinoma. The results from these histochemical studies established that the cell of origin in both the BALB/c carcinoma and the scirrhous-like carcinoma was the mammary epithelial rather than the myoepithelial cells. Furthermore, these results indicated that the MCF-8 cell line was derived from the epithelial component of the primary BALB/c carcinoma. These conclusions, which were based on histochemical study, were supported by the presence of intracisternal type A viral particles in the epithelial cells of the primary BALB/c carcinoma, the MCF-8 cells in culture, and the epithelial cells of the scirrhous-like carcinoma. Thus, the enzymatic markers were specific for cell type and remained unchanged by the process of cell transformation.
Cancer Res 1977 Apr
PMID:Adenosine triphosphatases as histochemical markers for the cell of origin in experimental mammary carcinoma. 19 Nov 76

Electron histochemical studies show that changes in the nucleoside triphosphatase activity in plasma membranes of cancer cells can proceed in different directions. Some cells show a high activity of magnesium-dependent NTPase over the whole membrane surface (perimeter), while others have a low enzymic activity which is present only in certain regions of the membranes, the remaining cells possessing no enzyme activity at all. These changes are not strictly characteristic of cancer cells alone.
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PMID:Hydrolysis of nucleoside triphosphate in plasma membranes of the hepatocytes of normal, regenerating and foetal livers and in cancer cells of hepatomas. 19 42

Adenosine triphosphatase (ATPase) activities of sonically prepared submitochondrial particles of rat liver and Morris Hepatoma 3924A were compared as a function of changes in temperature. On Arrhenius plots, a discontinuity at 18 degrees was observed for the rat liver mitochondrial ATPase, while the hepatoma mitochondrial ATPase revealed a discontinuity at 20.4 degrees. Values for energy of activation of the rat liver and hepatoma mitochondrial ATPases were comparable below the break (34.5 and 35.5 kcal/mole, respectively) and above the break (11.6 and 9.2 kcal/mole, respectively). Solubilization of the mitochondrial membrances with Triton X-100 resulted in constant and similar values of energy of activation for the ATPases Km values of hepatoma and rat liver mitochondrial ATPases for adenosine triphosphate were similar in both the membrane-bound and solubilized states. The lack of uncoupler-stimulated ATPase activity in hepatoma mitochondria is apparently not due to membranous effects on the affinity of the ATPase for adenosine triphosphate.
Cancer Res 1977 Dec
PMID:Membranous effects on adenosine triphosphatase activities of mitochondria from rat liver and Morris hepatoma 3924A. 20 Mar 47


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