Effects of endosulfan and aldrin on muscle coordination and conditioned avoidance response in rats.

The deteriorative effects after chronic endosulfan exposure on muscle coordination, learning and memory of rats were compared with that produced by aldrin which has been reported to have similar effects in experimental animals. A rota-rod apparatus was used to study the muscle coordination and learning and memory were tested by recording the response to unconditioned and conditioned stimuli using a pole-climbing apparatus. Aldrin but not endosulfan inhibited motor coordination in both sexes. A greater motor deterioration occurred in male group. This finding, together with the previous data which shows inhibition by its metabolite of motor activity, suggests that its metabolic product is responsible for this action. Like aldrin, endosulfan inhibited both learning ability and conditioned avoidance response. A change in the activities of brain monoamines or inhibition of perception and reflexes or both were proposed for these behavioural effects, since the former was reported to be produced by both compounds and the latter was found to occur in aldrin treated rats.