Cortisol induction of metallothionein in primary culture of rainbow trout hepatocytes.

In the present experiment, metabolically active primary cultures of rainbow trout hepatocytes were utilized to study the inducibility of metallothionein after cortisol treatment. Glucocorticoid induction of metallothionein has previously only been demonstrated in mammalian systems. We now demonstrate the inducibility of rainbow trout metallothionein by cortisol treatment of primary hepatocytes. A 90% elevation above control levels was achieved within 8 days of treatment. Zinc treatment was performed to evaluate the system, and 100 microns zinc in the culture medium resulted in a 350% increase of the metallothionein levels. We conclude that primary culture of rainbow trout hepatocytes constitutes an efficient system for studies of MT induction kinetics.