Abstract
The effects of intraperitoneal administration of varying doses of cadmium on hepatic metal and xenobiotic detoxication systems in the plaice, Pleuronectes platessa, were studied. The results showed that above a threshold of ca. 2 μg Cd/g liver, metallothionein (MT) levels were increased but at high doses the sequestration capacity of induced MT was exceeded and at the highest dose tested (1 mg Cd/kg) MT induction/synthesis was reduced and hepatic Zn levels decreased. Cadmium injection strongly reduced cytochrome P-450 dependent ethoxyresorufin o-deethylase (EROD) activity and preliminary immunological studies indicated that this was due to a decrease in enzyme protein rather than direct inhibition of activity by Cd. At the sampling time of this study (6 days) there was no significant alteration in activity of the phase II enzyme, glutathione-s-transferase.