The anticonvulsant effects of diazepam and phenobarbital in prek1ndled and kindled cortical seizures

The effects of various doses of diazepam (0.5–4 mg/kg) and phenobarbital (15–60 mg/kg) were determined on prekindled (focal) and kindled (generalized) cortical seizures in the same rats. Only high sedating doses of diazepam or phenobarbital reduced the elicited afterdischarge duration (ADD) and behavioral response in the prekindled focal cortical seizure. Against the kindled seizure, both diazepam and phenobarbital showed a marked and statistically significant increase in effectiveness in all but the smallest doses tested. The ADD of the kindled cortical seizures was reduced to prekindled lengths by diazepam (1–4 mg/kg) or phenobarbital (30–60 mg/kg). The increased anticonvulsant effectiveness found in this study is similar to previous findings with diazepam and phenobarbital against prekindled and kindled amygdaloid seizures, but stands in contrast to findings with prekindled and kindled pentylenetetrazol seizures.