Effect of dieldrin on catalytic potential of field mouse Mus booduga brain acetylcholinesterase.

Substrate kinetics of acetylcholinesterase (AChE) were investigated in control and dieldrin-treated Mus booduga brains. Non competitive inhibition with respect to activation by acetylcholine was indicated by decreased maximal velocity (V) without change in Michaelis-Menten constant (Km). Activation energies (delta E) were found to be increased suggesting decreased efficiency of enzyme in dieldrin-treated mouse brains. Fall in the activity potential of AChE may account for the interference of dieldrin or its metabolites with the acetylcholine (ACh)--AChE system and deserve consideration in contributing to the neurotoxicity.