EFFECTS OF TRIPHENYLTIN ON THE POTENTIAL ACTIVITIES OF TRYPSINOGEN AND CHYMOTRYPSINOGEN OF RED-SEA BREAM

Organotin compounds have been used as anti-fouling reagents having hig h toxicity to aquatic organisms. In this study, in order to assess the toxic effects of triphenyltin on fish, potential activities of chymot rypsinogen and trypsinogen in the liver of red sea bream, Pagrus major , and the activities of chymotrypsin and trypsin in the intestine were determined. The red sea bream were exposed to triphenyltin ranging fr om 0.13 mu g/l to 3.23 mu g/l for up to 8 weeks, The potential activit ies of chymotrypsinogen and trypsinogen in the liver of exposed fish w ere much lower than those in the control fish, whereas the active form s of these enzymes in the intestine were not affected by the exposure to triphenyltin. The feeding activity of fish exposed to tiphenyltin o f 3.23 mu g/l was depressed. The results of the relationship between d iet amounts given and enzyme activities suggested that starvation caus ed a remarkable decrease in the potential activities of the zymogens i n the liver, suggesting the depression of potential activities of the zymogens in the liver of exposed fish was not caused by the change in feeding activity of fish but by the toxic effects of triphenyltin. The potential activities of the zymogens were influenced by the exposure to triphenyltin of 0.13 mu g/l for 4 weeks.