[Effect of a Ca-channel blocker, ryodipine, on focal and generalized epileptic activity]

The experiments were performed on 102 freely moving Wistar rats. Epileptic foci were produced by the application of a filter paper soaked in a sodium benzylpenicillin solution (20,000 IU/ml) onto sensorimotor cortex. It was shown that an intraperitoneal administration of ryodipine (1,2 and 5 mg/kg) during a steady epileptic activity (EA) resulted in suppression of EA in most animals. Antiepileptic effect of ryodipine was manifested by a decreased frequency and amplitude of interictal discharges and a less frequent appearance of ictal discharges (ID). Prior administration of ryodipine (2 mg/kg) 30 min before producing the focus of EA resulted in an increased latency and decreased number of ID, and shortening of the duration of the focus of EA. Generalized convulsions were induced by intraperitoneal of pentylenetetrazol (60 mg/kg). Ryodipine (2 mg/kg, 30 min before pentylenetetrazol) increased latency to first convulsive episodes and delayed the development of generalized tonic-clonic seizures.