Effect of propranolol and nifedipine on maximal electroshock-induced seizures in mice: Individually and in combination

A comparative effect of propranolol and nifedipine administered individually and in combination at graded dose levels; and that of phenytoin at 30 mg kg^-1 on maximal electroshock (MES)-induced seizure in mice was investigated. Propranolol in doses of 10 mg kg^-1 and 20 mg kg^-1, and nifedipine in doses of 8 mg kg^-1 and 16 mg kg^-1 significantly modified MES activity. Propranolol (40 mg kg^-1), and a combination of propranolol (20 mg kg^-1) and nifedipine (8 mg kg^-1), produced antiMES activity, which was comparable to that of phenytoin (30 mg kg^-1). In mice treated with propranolol and nifedipine combination, the tonic flexor and tonic extensor phase ratios (F/E ratio) were significantly higher than individual drug responses. Our findings suggest that a combination of propranolol and nifedipine has either synergistic or an additive effect in controlling MES-induced seizures in mice.