Pesticide-induced changes in hepatic microsomal enzyme systems. Some effects of 1,1-di( p-chlorophenyl)-2,2,2-trichloroethane (DDT) and 1,1-di( p-chlorophenyl)-2,2-dichloroethylene (DDE) in the rat and Japanese quail

Abstract

Hepatic microsomal protein, cytochrome P-450, aniline hydroxylase, aromatic nitroreductase, phenyl benzoate esterase and total vitamin C, as well as tissue residue levels were measured following the feeding of low levels of 1,1-di( p-chlorophenyl)-2,2-dichloroethylene (DDE) or 1,1-di( p-chlorophenyl)-2,2,2-trichloroethane (DDT) to rats and Japanese quail. Changes in the factors measured were more readily related to the tissue residue levels than to the dietary feeding levels. It is suggested that DDE is a more potent inducer of microsomal protein, cytochrome P-450 and aniline hydroxylase in both species, than DDT fed at the same level, and the effects of DDT were best expressed in terms of the resulting DDE residue levels. Aromatic nitroreductase was not induced by feeding either DDT or DDE, and phenyl benzoate esterase levels showed a biphasic effect following DDE feeding. Vitamin C levels were raised more by DDT than DDE in both species. Residue levels were considerably higher in the quail than in the rat fed at the same rate. Basal levels of all the factors measured were higher in the rat and induction generally occurred to a greater extent and at a lower tissue residue level than in the quail.