TIME-COURSE STUDIES OF THE BIOTRANSFORMATION ENZYMES IN CONTROL RAINBOW-TROUT WHEN ADJUSTING TO NEW HABITATS

Hepatic monooxygenase enzyme activities and relative cytochrome P4501A protein content were measured to evaluate the time-course alterations in rainbow trout after change in living habitat. Fish were transferre d from one fish farm to the tanks of another hatchery and/or into cage s kept in a lake. In the new habitats, cytochrome P450-dependent enzym e activities in rainbow trout decreased, and were at their lowest leve ls after two or three weeks in the summer. Later the activities partly reversed. The immunodetection of cytochrome P4501A protein expressed a similar trend as for catalytic monooxygenase activities.