title: Expression of hepatic and ovarian cytochrome P450 during estrous cycle in rats.
abstract: It is known that gender differences in drug metabolism are largely attributed to changes in sex and growth hormones. Serum concentrations of estradiol, progesterone, prolactin, follicle-stimulating hormone, and luteinizing hormone change markedly during the human menstrual cycle and the rat estrous cycle. However, little information is available regarding the effects of the human menstrual cycle or the rat estrous cycle on expression and activity of cytochrome P450 (CYP) isoforms. The present study was carried out to determine the expression and activity of CYP-dependent drug-metabolizing enzymes in the liver and ovary during the estrous cycle. The expression and activity of microsomal CYP isoforms (CYP1A1, CYP1A2, CYP1B1, CYP2B1, CYP2C11, CYP2C12, CYP2E1, CYP3A1, CYP3A2, and CYP4A), cytochrome b(5) and NADPH-dependent CYP reductase in the liver and ovary were measured in female rats in diestrus and proestrus. Our results indicated that hepatic and ovarian expression and activity of CYP isoforms, cytochrome b(5), and NADPH-dependent CYP reductase were not different between diestrus and proestrus, although serum estradiol concentration and uterus weight were markedly increased in the proestrus phase. These results suggest that the cytochrome P450-dependent system is not sensitive to changes in the estrous cycle, and further studies are warranted to determine the effects of the estrous cycle on in vivo metabolism of xenobiotics.
authors: College of Pharmacy and RCTCP, Chungnam National University, Yuseong-gu, Daejeon, Republic of Korea.
authors: Sang Yoon
authors: SY
authors: Lee
authors: Soo Jin
authors: SJ
authors: Oh
authors: Kang Uk
authors: KU
authors: Yun
authors: Hwan Mook
authors: HM
authors: Kim
authors: Bong-Hee
authors: BH
authors: Kim
authors: Kiho
authors: K
authors: Lee
authors: Sang Kyum
authors: SK
authors: Kim
mesh_terms: D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism*; D030762:Estrous Cycle / Q000502:physiology*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D007527:Isoenzymes; D008099:Liver / Q000201:enzymology*; D008861:Microsomes / Q000201:enzymology; D008862:Microsomes, Liver / Q000201:enzymology; D010053:Ovary / Q000201:enzymology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D007527:Isoenzymes; D003577:Cytochrome P-450 Enzyme System