The effect of chronic cyclodiene insecticide treatment on some pharmacological actions of diazepam in rats

The sedative and hypnotic effects of diazepam were tested in rats following chronic treatment with subconvulsive doses of the cyclodiene insecticides, endosulfan and aldrin. The anticonvulsant effect of diazepam was determined on picrotoxin-induced convulsions in insecticide-treated and control animals. Both endosulfan and aldrin promoted the convulsant action of picrotoxin indicating that the insecticides were able to show proconvulsant action following chronic administration. Interestingly, the protective effect of diazepam against picrotoxin-induced convulsions was greater in endosulfan- and aldrin-treated animals than in control animals. The sedative and hypnotic effects of diazepam were also increased in insecticide-treated animals. The mechanisms involved in the interaction were discussed with the support of the findings reported by the present and other investigators on the central and hepatic effects of chronic endosulfan and aldrin treatment.