Action of clonazepam and clorazepate on cortical self-sustained after-discharges in the rat.

Self-sustained after-discharges (SSADs) induced by electric stimulation of the sensorimotor cortex in rats exhibited under control conditions a significant progressive prolongation with repeated stimulations. Clonazepam not only blocked this increase in duration but it suppressed and/or abolished SSADs in a dose-dependent manner. Clorazepate in the lowest dose used (10 mg/kg) did not change SSADs. The two higher doses (25 and 50 mg/kg) blocked the prolongation of the 4th SSAD, i.e. this effect had a relatively long latency.