Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.9 (glucose-6-phosphatase)
 3,081 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rat liver fixed with dimethylsuberimidate (DMS) was studied to investigate the use of diimidoesters as dixatives for light and electron microscopic cytochemistry. Paraffin sections of liver fixed with DMS at pH 9.5 were weakly stained with the ninhydrin-Schiff procedure, indicating extensive reaction of NH3+ groups with the fixative. Nuclei were strongly strained by the Feulgen procedure, with no background [corrected] reaction. In contrast, glutaraldehyde fixation resulted in a significant background reaction in the cytoplasm and nuclei in controls for the Schiff-based stains. DMS-fixed liver stained intensely for glycogen with the Periodic acid-Schiff procedure, and biochemical analysis of glycogen retention and extractability indicated that DMS retained considerably more glycogen in sections than glutaraldehyde. DMS-fixed liver incubated for thiamine pyrophosphatase activity revealed reaction product in ER cisternae, Goli saccules and bile canaliculi. Peroxisomes were strongly reactive for catalase activity after incubation in diaminobenzidine medium, and reaction product of glucose-6-phosphatase activity was considerably greater following DMS fixation than after glutaraldehyde. Biochemical studies revealed up to twice as musch residual activity of glucose-6-phosphatase after DMS fixation. These results suggest that DMS may be useful as a primary fixative for certain cytochemical procedures.
J Histochem Cytochem 1976 Sep
PMID:Tissue fixation with diimidoesters as an alternative to aldehydes. II. Cytochemical and biochemical studies of rat liver fixed with dimethylsuberimidate. 6 Dec 39

Golgi-rich fraction was isolated from Harding-Passey mouse melanoma by centrifugation through the discontinuous sucrose density gradient and its properties were compared with those of the same fraction isolated from rat liver. The specific activity of UDP-galactose: N-acetylglucosamine galactosyltransferase was 35 times higher in the melanoma Golgi fraction than in the melanoma homogenate and was a half that in the rat liver Golgi fraction. The specific activities of marker enzymes for other subcellular components such as 5'-nucleotidase, acid phosphatase and glucose-6-phosphatase in the melanoma Golgi fraction were all one-third those in the melanoma homogenate. Electron micrographs of the negatively-stained Golgi fractions of melanoma and liver revealed the presence of a system of tubules, vesicles and plate-like center regions which are known as components of Golgi apparatus. Tyrosinase activity was found to be present in this fraction of mouse melanoma, but its specific activity was lower than that in the rough or smooth surface membrane fraction or in the melanosome fraction.
Tohoku J Exp Med 1978 Sep
PMID:Isolation and characterization of a Golgi-rich fraction from the Harding-Passey mouse melanoma. 10 Aug 98

Differential centrifugation was applied to adult and foetal liver of monkey. Obtained fractions were: F1 (800 X g); F2 (12 500 X g); F3 (200 000 X g); and cell sap. Analysis of chemical compounds of these fractions shows that: (1) adult and foetal nucleic acids levels are similar; (2) there are more proteins in adult than in foetal hepatocytes; (3) most of the glycogen is located in F3; the foetal level is twenty times higher than the adult level. Plasma membrane enzymes (5'-nucleotidase, adenylate cyclase) show a nucleomicrosomic distribution. The distribution of alkaline phosphatase is not significant. Mitochondrial enzymes (monoamine oxydase, succinate cytochrome c reductase, cytochrome oxydase) are enriched in F2 without any sedimentation in F3. There is more malate dehydrogenase liberated in cell sap during foetal liver fractionation. This indicates the foetal mitochondria are more sensitive to the homogenisation method. Lysosomal enzymes (acid phosphatase, N-acetylglucosaminidase) are enriched in F2. The same observation for N-acetylglucosaminidase as for malate dehydrogenase leads to the same conclusion for foetal lysosomes. Endoplasmic reticulum and Golgi enzymes (glucose-6-phosphatase and related phosphotransferase activity, NADPH-cytochrome c reductase and sialytransferase) are much enriched in F3. Thus this fraction F3 is pure enough to allow the observation of the modification produced on endoplasmic reticulum and Golgi apparatus during foetal and neonatal development.
Biochim Biophys Acta 1979 Sep 20
PMID:[Comparative study of microsomal enzymic activities in adult and foetal monkey hepatocytes (author's transl)]. 11 30

1. Cataract formation in streptozotocin-induced diabetes in rats was reduced by approximately 85% when a diet rich in maize oil (300 g/kg diet) (fat diet) was given, thus confirming results of earlier studies. However, the concentration of sorbitol in the lens of diabetic animals remained high, the values for diabetic rats given the standard diet and the fat died being 65 and 40 mumol/g protein respectively. 2. With the standard diet, the fatty acid profile of the triglycerides of the epididymal fat pads was characterized by a greater relative proportion of saturated fatty acids for the diabetic animals compared to that for the normal animals. The fat diet moderated the tendency towards saturation in the diabetic animals. 3. The fat diet had other effects on the diabetic animals; these included a reduced mortality rate, increased body-weight, a decrease in the daily water intake, and in the daily urinary excretion of glucose and urea. 4. In the diabetic animals the fat diet had no effect on the specific activities in the liver of hexokinase (EC 2.7.1.1), glucokinase (EC 2.7.1.2), phosphofructokinase (EC 2.7.1.11) and pyruvate kinase (EC 2.7.1.40). However, the specific activity of glucose-6-phosphatase (EC 3.1.3.9) was reduced, while that of malate dehydrogenase (decarboxylating) (NADP) (EC 1.1.1.40) was increased. The NAD+:NADH ratio, as calculated from liver pyruvate and lactate concentrations, tended to increase. 5. The results suggested that the fat diet moderated the long-term metabolic effects of diabetes.
Br J Nutr 1976 Sep
PMID:The effect of an unsaturated-fat diet on cataract formation in streptozotocin-induced diabetic rats. 13 11

Three groups of 6 male chicks each were fed a commercial diet and were given drinking water which contained either 0, 150 or 300 mug. of mercury/ml. as mercuric chloride from hatching to 3 weeks of age. The chicks were killed, the livers were removed and weighed, and the activities of selected enzymes were measured in the 800 X gav supernatant fractions of the liver homogenates. Liver weights were depressed from control values in chicks receiving 300 p.p.m. mercury but not in chicks receiving 150 p.p.m. Fatty acid synthetase specific activity was depressed by both levels of added mercury, but microsomal fatty acid elongation was depressed only by 300 p.p.m. of mercury. Both levels of added mercury stimulated acid phosphatase specific activity. The speecific activities of cytochrome c oxidase, glucose-6-phosphatase and 6-phosphogluconate dehydrogenase were unaffected by added mercury. The data support the hypothesis that mercury administration does not result in generalized hepatotoxicity.
Poult Sci 1975 Sep
PMID:Mercuric chloride effects on the activities of some hepatic enzymes in chicks. 17 40

Pretreatment of male rats with Aroclor 1254 at a dose of 25 mg/kg i.p. for 6 days resulted in potentiation of the hepatotoxicity of inhaled carbon tetrachloride (CCl4) as evidenced by a decrease in liver glucose-6-phosphatase and elevations of serum glutamic oxalacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), isocitrate dehydrogenase, and sorbitol dehydrogenase. Aroclor 1254 alone did not demonstrate hepatotoxicity. Aroclor 1254 administration resulted in large increases in cytochrome c reductase, cytochrome P-450 (448) AND P-Nitroanisole demethylation. Subsequent exposure to CCl4 vapor resulted in over 70% decreases in the latter two parameters. The potentiation was dose-dependent with a dose of 5 mg/kg or higher being effective. Aroclor 1260 administration gave results similar to those of Aroclor 1254, but Aroclor 1221 enhanced CCl4 toxicity to a lesser extent.
Toxicology 1975 Sep
PMID:Potentiation of carbon tetrachloride hepatotoxicity in rats by pretreatment with polychlorinated biphenyls. 17 1

Normal and alloxan-diabetic rats were fed ground Purina Laboratory Chow with or without 500 ppm of Aroclor 1254 (AR) ad lib for 2 weeks. In both normal and diabetic rats, AR administration decreased food consumption, weight gain and blood glucose concentration, and increased liver weight, liver:body weight ratio, total liver lipid, liver protein and malic enzyme (ME) activity. In the normal rat, AR increased the concentrations of acetoacetate and beta-hydroxybutyrate in blood, but in the diabetic rat the concentrations were markedly reduced. AR administration decreased the activity of phosphoenolpyruvate carboxykinase (PEPck) in normal liver and the activities of pyruvate carboxylase (PC), PEPck and glucose-6-phosphatase (G6Pase) in diabetic liver.
Toxicology 1975 Sep
PMID:The effects of a polychlorinated biphenyl mixture (Aroclor 1254) on liver gluconeogenic enzymes of normal and alloxan-diabetic rats. 17 2

The effects of two environmental temperatures (T; 16 degrees and 31 degrees), five diet dilutions (D; 0%, 12.5%, 25%, 37.5% and 50%), and five daily treadmill running periods (E; 10 minutes, 40 minutes, 70 minutes, 100 minutes, and 130 minutes) upon enzyme activities of liver and adipose tissue of male rats were observed. Liver enzymes studied were glucose-6-phosphatase (G6Pase), 6-P-gluconate dehydrogenase (6PGD), glucose-6-phosphate dehydrogenase (G6PD), fructose diphosphatase (FDPase), NADP-isocitrate dehydrogenase (ICDH), and malic enzyme (ME). Adipose tissue (epididymal fat) enzymes (6PGD, G6PD, and ME) were studied as well as the in vitro incorporation of the 14C of [U-14C] glucose into liberated 14CO2 and into the triglycerides, free fatty acids, and total lipids by adipose tissue slices. Equations describing regression surfaces for these responses (expressed as units/100 g body weight) could contain significant linear coefficients of the independent variables (T, D, and E), their first order interactions, and quadratic coefficients for D and E. Significnat regression coefficients for activities of liver enzymes associated with increased lipogenesis (6PGD, G6PD, and ME) produced response surfaces with conformations generally concave downward. All enzymes possessed positive and negative linear and quadratic coefficients for D which caused response surfaces to be concave downward with respect to that variable. Also, 6PGD and G6PD (positive linear and negative quadratic coefficients for E) exhibited response surfaces concave downward with respect to E. Additionally, 6PGD showed greater activity at 31 degrees than at 16 degrees while G6PD showed no effect of temperature on activity. Liver ICDH, probably important in supplying reducing equivalents for fatty acid synthesis, evidenced response surfaces almost identical to those for 6PGD. Significant regression coefficients for activity of liver enzymes associated with increased gluconeogenesis (FDPase and G6Pase) produced for FDPase a response surface concave downward with respect to both D and E with greater values at 31 degrees than at 16 degrees; but for G6Pase non-concave surfaces with lesser values at 31 degrees than at 16 degrees. Significant regression coefficients for activities of adipose enzymes associated with increased lipogenesis produced for 6PGD a response surface concave upward due to negative linear and positive quadratic coefficients for both D and E. For G6PD and ME regression surfaces were concave upward with respect to E, but these were modified by positive and negative linear coefficients, respectively, for D. Significant regression coefficients for incorporation of the 14C of glucose into triglycerides and free fatty acids of adipose tissue slices and their production of 14CO2 yielded response surfaces concave upward with respect to E (negative linear and positive quadratic coefficients). In addition, the surface for free fatty acids was concave upward with respect to D. The 14CO2 production was greater at 16 degrees than at 31 degrees...
J Nutr 1976 Sep
PMID:Effects in the rat of environmental temperature, diet dilution, and treadmill running on liver and adipose enzymes and metabolism of 14C-glucose: a multiple regression analysis. 18 37

In older patients with glucose-6-phosphatase deficiency adenomatous nodules develop within the liver parenchyma. Investigation of eight such patients, age 3 to 28 years, using radioisotopic scans, has demonstrated areas of depressed isotope uptake in the liver in all except the one preteenaged child. Three patients were further studied with hepatic angiograms and liver biopsy specimens. A diffuse nodularity, more widespread than apparent on isotopic scans, was demonstrated on angiograms. Although initial histologic study in each case showed adenomatous tissue without evidence of neoplasm, the development of hepatocellular carcinoma in one of our patients and in others from the literature suggests that the nodules may be premalignant.
JAMA 1976 Sep 27
PMID:Hepatic adenomata with type 1 glycogen storage disease. 18 26

A rat liver nuclear envelope fraction isolated essentially by the technique of Monneron et al. (J. Cell Biol. 55, 104-125 (1972) is characterized by high levels of glucose-6-phosphatase and 5'-nucleotidase. A broadly specific nucleoside triphosphatase activity is present. Cytochromes b5 and P-450 as well as NADPH- and NADH-cytochrome c reductase activities are present but at lower levels than found in microsomes. Cytochrome c oxidase activity is low. RNA polymerase activity is absent from the nuclear envelope fraction. Cytochemistry shows that glucose-6-phosphatase activity is strong and restricted to the nuclear envelope of nuclei. 5'-Nucleotidase shows weak reaction deposit in whole nuclei but in contrast gives clear reaction deposit in isolated nuclear envelopes. Cytochemical reaction deposit due to nucleoside triphosphatase activity is not restricted to the nuclear envelope but is found to a larger extent within the nucleus.
Biochim Biophys Acta 1976 Sep 21
PMID:An enzymic analysis of a nuclear envelope fraction. 18 34


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