using several concentrations of eight anticonvulsant drugs in clinical use ( carbamazepine , clonazepam , phenytoin , phenobarbital , ethosuximide , primidone , sodium valproate , and d , l-gamma-vinyl gaba ) , we studied their abilities in vitro to displace ( 35s ) t-butylbicyclophosphorothionate ( 35s-tbps ) from its binding site in a homogenate of rat brain .
C0031412
phenobarbital
C0033148
primidone