Organ-specific ATPase and phosphorylase enzyme activities in a food fish exposed to a carbamate insecticide and recovery response.

The acute effect of carbofuran, a carbamate insecticide, was studied on adenosine triphosphatase enzymes in gill, kidney, liver and muscle tissues of a food fish, Clarias batrachus. Glycogen and glycogen phosphorylase were investigated in gill and kidney only. Thirty-six fish were exposed to sublethal concentration (7.6 mg/L) for 6 days. After 6 days, 18 fish were released into freshwater in order to study the recovery response. Eighteen fish were kept in clean water as control. Tissues were isolated from control, exposed and recovery fish at the end of 1, 3 and 6 days and used for the assay of enzymes. Total ATPase was inhibited in kidney and muscle tissues throughout the exposure period, whereas branchial and hepatic tissues showed initial induction followed by inhibition. Na(+)-K(+) ATPase activity was induced in gill till day 3, whereas in other tissues inhibition was throughout the exposure period. Mg(+2) ATPase activity was inhibited in all tissues except liver. When the fish were released into freshwater, liver recovered almost to control values and other tissues showed organ-specific response. Glycogen content of gill increased initially followed by decrease, and in kidney initial decrease was noted. The recovery response was more in kidney than in gill. Induction in the activity of glycogen phosphorylases was observed in kidney, whereas gill tissue showed mixed response. Recovery was not observed in phosphorylases. Thus, the results of the present study demonstrated the acute effect of carbofuran on a food fish and organ-specific recovery response to insecticidal treatment.