The effect of PCB on the induction of cytochrome P450 enzyme, detected by monoclonal antibody against the P450IA1 gene products, in barn owl and marsh turtle hepatic microsomes

Induction of P450 species belonging to the P450IA1 gene family was demonstrated in liver microsomes of the barn owl Tyto alba and the marsh turtle Mauremys caspica rivulata, after treatment with Aroclor 1254, using immunoblotting technique with monoclonal antibody (Mab) specific to P450IA1 (anti scup P450E, 1-12-6 Mab). P450IA1 could hardly be detected in barn owls collected from their natural habitat. Significant induction (P < 0.05), of up to three times, in the content of the barn owls hepatic microsomal P450IA1 was recorded after intraperitoneal injection of Aroclor 1254, although the proportion of P450IA1 from P450 content, did not exceed 5 percent. The content of P450IA1 in liver microsomes of marsh turtles collected from their natural habitat was relatively high, and values up to 225 pmol/mg protein were recorded. Treatment with Aroclor 1254 increased the mean content of P450IA1 in the turtle livers up to 5 times, and the proportion of P450IA1 from total hepatic P450 was about 20 percent.