Variation and Location of Cytochrome P450 Isoenzymes in Various Organs Including the Liver of Rats Treated with Methylbenzylnitrosamine, N, N-dibutylnitrosamine, and 1, 2-Dimethylhydrazine

Abstract

Variation and location of cytochrome P450 isoenzyme expression in various organs of male F344 rats treated with 1, 2-dimethylhydrazine (DMH), N, N-dibutylnitrosamine (DBN), and methylbenzylnitrosamine (MBNA) were immunohisto-chemically and biochemically investigated. The animals received MBNA (6mg/6ml/kg b.w. i.p.) in corn oil, DBN (400mg/4ml/kg b.w. i.p.) in distilled water with Tween 80, or DMH (40mg/4ml/kg b.w. i.p.) dissolved in saline. All animals were sacrificed at hours 15 after administration of the test compound. CYP2C11 was immunohistochemically observed in the centrilobular areas of the liver in rats treated with both DBN and DMH. Western blotting analysis, however, showed significantly decreased level of CYP2C11 protein in the liver of rats treated with DBN. CYP2D1 was immunohistochemically observed in periportal areas of the liver in rats treated with MBNA. The present investigation demonstrated that expression of cytochrome P450 isoenzymes can modulate exogenous agents in the liver.