title: Biological responses of xenobiotic metabolizing enzymes to lead exposure in cultured H4IIE rat cells.
abstract: This study was undertaken to investigate the constitutive response of xenobiotic metabolizing enzymes (XMEs) to lead (Pb2+) exposure in cultured rat liver (H4IIE) cell lines. Phase I enzymes such as CYP1A1 and CYP1A2 had mRNA expressions that were slightly induced after exposure to low concentrations of Pb2+; however, under higher concentrations of Pb2+, the mRNA expressions of CYP1A1 and CYP1A2 were significantly down-regulated. These effects were in correspondence with AhR mRNA expression. Phase II enzymes had mRNA expressions that were reduced upon exposure to Pb2+. Metallothionein mRNA expression was induced after treatment with Pb2+ in a dose-dependent trend. In conclusion, Phase I and II enzymes were significantly modulated upon lead exposure indicating some toxicological implications for lead exposure in cultured H4IIE cells.
authors: Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, N18, W9, Kita-ku, Sapporo 060-0818, Japan.
authors: Wageh Sobhy
authors: WS
authors: Darwish
authors: Yoshinori
authors: Y
authors: Ikenaka
authors: Mayumi
authors: M
authors: Ishizuka
mesh_terms: D000818:Animals; D002460:Cell Line; D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D007854:Lead / Q000494:pharmacology*; D008668:Metallothionein / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats
chemical_list: D065607:Cytochrome P-450 Enzyme Inhibitors; D012333:RNA, Messenger; D007854:Lead; D003577:Cytochrome P-450 Enzyme System; D008668:Metallothionein