title: Influence of partial hepatectomy in rats on the activity of hepatic microsomal enzymatic systems.
abstract: The influence of partial hepatectomy on the activity of the hepatic microsomal enzymatic systems was determined in rats. Cytochrome P-450, cytochrome b5, four mixed functional oxidase (MFO) activities (microsomal aniline hydroxylase, p-nitroanisole O-demethylase, aminopyrine N-demethylase and NADPH cytochrome c reductase) and glutathione levels were measured in unhepatectomized rats (control group) and in hepatectomized rats 12 h, 24 h, 3 days and 6 days after 70% hepatectomy. Following surgery the remaining lobes of the liver grow rapidly in order to restore the original liver mass. Partial hepatectomy significantly reduces cytochrome P-450 and b5 content in the remaining liver as well as the four MFO activities studied. But when the enzymatic systems are expressed as nmoles/mg microsomal protein, only cytochrome P-450 shows statistical differences. The hepatic biotransformation capacity of drugs and xenobiotics decreases during the regeneration period due to the reduction of hepatic mass rather than because of a reduction of their metabolic capacity. Glutathione levels are increased after partial hepatectomy but increased glutathione-dependent protector mechanisms are not expected.
authors.affiliation: Laboratory of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, University of the Basque Country, Spain.
authors.forename: A M
authors.initials: AM
authors.lastname: Maza
authors.forename: A R
authors.initials: AR
authors.lastname: Gascon
authors.forename: M B
authors.initials: MB
authors.lastname: Calvo
authors.forename: R M
authors.initials: RM
authors.lastname: Hernandez
authors.forename: M A
authors.initials: MA
authors.lastname: Monte
authors.forename: J J
authors.initials: JJ
authors.lastname: Marin
authors.forename: A
authors.initials: A
authors.lastname: Dominguez-Gil
authors.forename: J L
authors.initials: JL
authors.lastname: Pedraz
mesh_terms: D000633:Aminopyrine N-Demethylase / Q000378:metabolism; D000815:Aniline Hydroxylase / Q000378:metabolism; D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D015786:Cytochromes b5 / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D006498:Hepatectomy; D008099:Liver / Q000737:chemistry / Q000254:growth & development / Q000601:surgery; D008115:Liver Regeneration / Q000502:physiology; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology*; D009251:NADPH-Ferrihemoprotein Reductase / Q000378:metabolism; D010090:Oxidoreductases, O-Demethylating / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D015431:Weight Loss
chemical_list: D015786:Cytochromes b5; D003577:Cytochrome P-450 Enzyme System; D010090:Oxidoreductases, O-Demethylating; C019704:anisole O-demethylase; D000815:Aniline Hydroxylase; D000633:Aminopyrine N-Demethylase; D009251:NADPH-Ferrihemoprotein Reductase; D005978:Glutathione