[GABA-ergic component in the action of the tranquilizing agent mebikar].

The paper is concerned with studies into the effect of the tranquilizer mebicar, a derivative of tetra-N-alkyl bicyclic bisureas, on the GABA-ergic system. The drug in doses of 250-1500 mg/kg (1/15-1/2 LD50) increased the preconvulsive period upon thiosemicarbazide administration, inconsistently changed the effects of picrotoxin and displayed antagonism in regard to bicucullin. Upon 2-week administration the drug reduced the GABA content in the rat brain. A hypothesis is advanced of mebicar-associated facilitation of the inhibitory GABA-ergic transmission.