IONIC LEAD, BUT NOT OTHER IONIC METALS (NI2-METHOXY-4-AMINOAZOBENZENE-MEDIATED CYTOCHROME P450IA2 (CYP1A2) INDUCTION IN RAT-LIVER(, CO2+ AND CD2+), SUPPRESSES 2)
M. Degawa et al., IONIC LEAD, BUT NOT OTHER IONIC METALS (NI2-METHOXY-4-AMINOAZOBENZENE-MEDIATED CYTOCHROME P450IA2 (CYP1A2) INDUCTION IN RAT-LIVER(, CO2+ AND CD2+), SUPPRESSES 2), Biological & pharmaceutical bulletin, 18(9), 1995, pp. 1215-1218
Male F344 rats mere pretreated with lead nitrate, nickel chloride, cob
alt chloride or cadmium chloride, and their effects on the induction o
f cytochrome P450 (CYP) enzymes, mainly CYP1A2 enzyme, with 2-methoxy-
4-aminoazobenzene (2-MeO-AAB) in the livers were comparatively examine
d by enzymatical, immunochemical, and molecular biological methods. Wh
en rats were pretreated with each ionic metal, the total CYP amount in
the liver microsomes decreased, as compared with that of rats treated
with 2-MeO-AAB alone. However, among the ionic metals used only lead
reduced the levels of the mRNA and protein of CYP1A2 induced with 2-Me
O-AAB in the rat liver, and decreased the microsomal activity (per CYP
) for CYP1A2-mediated mutagenesis. Furthermore, ionic lead, but not ot
her ionic metals, showed an ability to induce a placental form of glut
athione S-transferase (GST-P). The level of CYP1A2 induced with 2-MeO-
AAB was decreased along with increase in that of the induced GST-P.