[Effect of diazepam on the Na, K-ATPase state in a penicillin--induced hyperactivity focus in the cerebral cortex]

Intramuscular injection of diazepam to rats at doses of 0.01 and 2 mg/kg 25-30 min after penicillin application to the rat brain cortex leads to alteration of periodic appearance of epileptic seizures (ES), to changes in the seizure pattern, and to emergence of periodic acceleration of epileptiform discharges (ED). Injection of diazepam at a dose of 2 mg/kg 20 min before penicillin application results in the reduction of ED latency in the epileptogenic focus and in a decrease in their frequency before seizures as compared to the control animals without diazepam injection. ES appear irregularly, their quantity is markedly reduced while duration is increased. Diazepam injection leads to disappearance of the rat moving reaction during ER and ES. In vivo experiments diazepam (2 mg/kg) does not influence brain cortex Na, K-ATPase of crude synaptosomes. However, diazepam leads to an increase in Na, K-ATPase activity both in the primary and dependent secondary epileptogenic foci. It is suggested that the anticonvulsant action of diazepam may be underlain by its activating effect on Na, K-ATPase of neuronal membranes in the epileptogenic focus.