Deldrin and parathion interaction in the prostate and liver of the mouse

The oral administration of dieldrin (1.25 mg/kg daily x 5 or 10) and/or parathion (5.2, 2.6, or 1.3 mg/kg daily x 5 or u0) caused significant alterations in the metabolism of [1,2-3H]testosterone by the anterior prostate gland and by the hepatic microsomal enzyme system in the mouse. A 5-day parathion treatment followed by another 5-day treatment with dieldrin led to significant increases in the levels of [3H]androstanediol a [3H]androstenedione formed by the prostate gland in vitro. Dieldrin alone, dieldrin plus parathion, or dieldrin administration followed by parathion treatment caused significant reductions in the levels of [3H]androstenedione formed by hepatic microsomal enzymes. Concomitantly, significant increases were observed in hepatic 7alpha-and 6beta-testosterone hydroxylase activities in animals treated with parathion followed by dieldrin administration. The present findings revealed that the administration of parathion or dieldrin leads to changes in the metabolism of male sex hormones in mouse liver and sex accessory organs. In addition, the simultaneous administration of parathion and dieldrin leads to an interaction that can alter the biologic effects of either compound.