title: [The level and activity of molecular forms of monooxygenase P-450b and P-450c during their separate and consecutive induction in the liver].
abstract: Studies with monospecific antibodies to individual forms of monooxygenases P-450b (phenobarbital-induced) and P-450c (3-methylcholanthrene-induced) by immunochemical, kinetic and spectral methods revealed differences in the dynamics of xenobiotic-induced changes in the content and monooxygenase activity of the total microsomal CO-binding hemoprotein and of its molecular forms. Correction was made in the estimation of the benzphetamine-demethylase and benzpyrene-hydroxylase activities based on the content of specific forms of P-450b and P-450c. Since consecutive injection of phenobarbital and 3-methylcholanthrene (or vice versa) is accompanied by selective induction of the corresponding isoforms and the redistribution of the relative content of P-450b and P-450c in the total pool of cytochrome P-450 in rat liver microsomes, a conclusion was drawn that these molecular forms are induced by different populations of hepatocytes. This conclusion was confirmed by data from immunohistochemical analysis.
mesh_terms: D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis*; D004790:Enzyme Induction; D005779:Immunodiffusion; D007527:Isoenzymes / Q000096:biosynthesis*; D008297:Male; D008748:Methylcholanthrene / Q000494:pharmacology; D008862:Microsomes, Liver / Q000201:enzymology*; D010634:Phenobarbital / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013379:Substrate Specificity
chemical_list: D007527:Isoenzymes; D008748:Methylcholanthrene; D003577:Cytochrome P-450 Enzyme System; D010634:Phenobarbital
vernacular_title: Soderzhanie i aktivnost' molekuliarnykh form monooksigenazy P-450b i P-450c pri ikh razdel'noĭ i posledovatel'noĭ induktsii v pecheni.