Interaction of carbaryl with acetylcholinesterase of the teleost,Clarias batrachus

Acetylcholinesterase (AChE, EC 3.1.1.7) of Clarias Batrachus, a fresh water teleost, was localised both in the paniculate and soluble fractions of cell‐free homogenate of the fish tissues. The paniculate bound enzyme could be solubilised using buffer containing Triton X‐100 resulting in maximum recovery of enzyme (88–92%) in the supernatant. Carbaryl at sublethal concentrations exerted an inhibitory effect on the level of AChE activity in the tissues of the fish. The inhibition was more pronounced when the fish was exposed with the subacute concentrations of the pesticide (1, 2 and 6mg/l) for 15 days than for 96 hr. There was much less difference between the inhibitory effects of carbaryl at 2 and 6 mg/1 concentrations for both treatment durations, except in gills where the inhibition was enhanced at increased concentration (6 mg/1). The interaction of carbaryl caused more inhibition of AChE activity in brain and gills than liver and muscle of C. batrachus.