The effects of electrical stimulation of the paleocerebellar cortex on penicillin-induced convulsive activity in rats.

Studies in Wistar rats in conditions of free behavior showed that low-frequency stimulation of the paleocerebellar cortex (nodulus, uvula) (10-12 Hz, 0.5 msec) was accompanied by activation of spike discharges induced by systematic application of benzylpenicillin sodium (3,000,000 IU/kg). Facilitation of the formation of ictal discharges was also seen. High-frequency electrical stimulation (100-300 Hz, 0.25 msec) of the same structure was accompanied by suppression of the generation of spike potentials and prevented the development of ictal potentials. The antiepileptic effect of electrical stimulation was seen in conditions of relatively low levels of convulsive activity. Electrical stimulation decreased the frequency and amplitude of spike potentials in the interstimulus intervals and decreased the total duration of epileptic foci. Repeated electrical stimulation of the paleocerebellum after electrocoagulation did not produce any changes in convulsive activity.