M. Degawa et al., IONIC LEAD, A UNIQUE METAL-ION AS AN INHIBITOR FOR CYTOCHROME P450IA2(CYP1A2) EXPRESSION IN THE RAT-LIVER, Biochemical and biophysical research communications, 200(2), 1994, pp. 1086-1092
Male F344 rats were treated with lead nitrate, nickel chloride, cobalt
chloride or cadmium chloride, and changes in the expression of cytoch
rome P450IA2 (CYP1A2) in the livers were assessed by enzymatical, immu
nochemical, and molecular biological methods. All ionic metals used si
gnificantly decreased total CYP amount in the liver microsomes. Howeve
r, among ionic metals used only lead showed inhibitory effects on the
microsomal activity for CYP1A2-dependent mutagenesis of aromatic amine
s and on the expression of mRNA and protein of the enzyme, indicating
that ionic lead is a unique inhibitor for the expression of CYP1A2 enz
yme in the rat liver. (C) 1994 Academic Press, Inc.