Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04040 (Catalase)
 3,577 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To evaluate the possible role of catalase in gastric ethanol metabolism in rats, we studied acetaldehyde formation from ethanol by gastric mucosal homogenate under various in vitro conditions. Homogenized rat gastric mucosa produced significant amounts of acetaldehyde in a time and ethanol concentration-dependent manner, even in the absence of added NAD. Both acetaldehyde formation and catalase activity peaked around the physiological pH, whereas alcohol dehydrogenase (ADH) activity was in that pH range low and reached peak values only at a higher pH of 9 to 10. Catalase inhibitors sodium azide (SA) and 3-amino-1,2,4-triazole (3-AT) had little effect on ADH activity but markedly decreased catalase activity and acetaldehyde formation (1 mM of SA to 56 +/- 13% of control, 5 mM of 3-AT to 67 +/- 3% of control; mean +/- SE). 4-Methylpyrazole decreased ADH activity significantly, but did not affect acetaldehyde formation. Heating of the homogenate at 60 degrees C for 5 min decreased ADH activity only slightly, but totally abolished catalase activity and reduced acetaldehyde formation to 39 +/- 3% of control. Addition of a H2O2 generating system (beta-D(+)-glucose + glucose oxidase] increased acetaldehyde formation in a concentration-dependent manner up to 8-fold of the control value. Our results strongly suggest that, in addition to ADH, catalase may play a significant role in gastric ethanol metabolism in rats.
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PMID:Role of catalase in rat gastric mucosal ethanol metabolism in vitro. 889 20

In the first pass methanol biotransformation three enzymatic systems: alcohol dehydrogenase (ADH), microsomal alcohol oxidising system (MEOS) linked with cytochrome P-450 and catalase are involved. Because of the toxicity of methanol, which is directly caused by its toxic metabolites, the major task in clinical toxicology is to inhibit each of these enzymes to protect human life. The aim of this investigation was to check the influence of some effective inhibitors of ADH and MEOS: 4-methylpyrazole, cimetidine, EDTA and 1,10-phenantroline on the activity of catalase with methanol as a substrate and the comparison with 3-amino-1,2,4-triasole. Catalase activity in rat hepatic homogenates was measured spectrophotometrically in vitro at physiological pH 7.4 and temp. 37 degrees C, assaying the degree of methanol oxidation according to Handler and Thurman. The quantity of arising formaldehyde was measured according with the method of Nash. Our results have shown that catalase activity was inhibited to different extents by all investigated compounds at concentrations of 10(-3) mol/l, 2 x 10(-4) mol/l, 10(-4) mol/l, 2 x 10(-5) mol/l, 10(-5) mol/l. 1,10-Phenantroline was found to be a highly effective inhibitor in comparison with aminotriasole. 4-Methylpyrazole, EDTA, 1,10-phenantroline and aminotriasole are catalase competitive inhibitors and cimetidine is non-competitive inhibitor. 4-Methylpyrazole has shown higher affinity to the enzyme than aminotriasole.
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PMID:[Activity of catalase after administration of some ADH and MEOS inhibitors: in vitro investigation in rat liver homogenates]. 1505 35