title: 3-Methylcholanthrene induction of enzymes in the vitamin K-dependent carboxylation system.
abstract: The effect of 3-methylcholanthrene on liver enzymes in the vitamin K-dependent carboxylation system has been investigated in normal rats and rats treated with the anticoagulant warfarin. It was found that 3-methylcholanthrene did not interfere with the anticoagulant function of the drug. Treatment of rats with 3-methylcholanthrene resulted in a 2.7-fold increase in liver cytosolic DT-diaphorase activity and a 1.5-fold increase in liver microsomal vitamin K-dependent carboxylase activity. A pathway for production of reduced vitamin K cofactor for the vitamin K-dependent carboxylase is catalyzed by DT-diaphorase and an as yet unidentified NADH-specific dehydrogenase(s). The data suggest that the unidentified enzyme(s) in the pathway is not induced by 3-methylcholanthrene.
mesh_terms: D015415:Biomarkers; D019735:Carbon-Carbon Ligases; D003600:Cytosol / Q000201:enzymology; D004790:Enzyme Induction / Q000187:drug effects; D008025:Ligases / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008748:Methylcholanthrene / Q000494:pharmacology*; D008862:Microsomes, Liver / Q000201:enzymology; D016660:NAD(P)H Dehydrogenase (Quinone); D011498:Protein Precursors / Q000378:metabolism; D011516:Prothrombin / Q000378:metabolism; D011808:Quinone Reductases / Q000378:metabolism; D014812:Vitamin K / Q000502:physiology*; D014859:Warfarin / Q000494:pharmacology
chemical_list: D015415:Biomarkers; D011498:Protein Precursors; D014812:Vitamin K; C008208:acarboxyprothrombin; D008748:Methylcholanthrene; D014859:Warfarin; D011516:Prothrombin; D016660:NAD(P)H Dehydrogenase (Quinone); D011808:Quinone Reductases; D008025:Ligases; D019735:Carbon-Carbon Ligases; C020660:glutamyl carboxylase