THE EFFECT OF MERCURY EXPOSURE ON LIVER MESSENGER-RNA TRANSLATABILITY AND METALLOTHIONEIN IN RAINBOW-TROUT

1. Young rainbow trout (Salmo gairdneri now known as Oncorhynchus mykiss) were exposed either to 0.2-mu-g-5-mu-g Hg2+/l for two weeks or to 5-mu-g-100-mu-g Hg/l for 4 days. 2. The mRNA translatability in vitro was uniformly elevated in liver of exposed fish. There was a 3-fold increase in the synthesis of 10-14 kD proteins but a lesser increase in total proteins, as analyzed by polyacrylamide gel electrophoresis. 3. Metallothionein levels in liver, measured by differential pulse polarography, were increased 3-fold at the highest exposure but to a lesser degree with lower exposure.