GABA-ergic mechanisms in the anticonvulsive activity of newly-synthesized barbiturates. I. Effects of barbiturates on the convulsive action of GABA-antagonists.

The anticonvulsive activity of seven newly-synthesized derivatives of barbituric acid, having a hydroxylamins groups substituted in second position, with respect to convulsive agents related with the GABA-ergic transmitter system: picrotoxin, bicuculline, thiosemicarbazide and 3-mercaptopropionic acid, was studied in experiments on mice. The anticonvulsive activity of these compounds in allylglycine-induced convulsions was investigated in experiments on rats, and was compared to that of well-known drugs, such as pentobarbital, phenobarbital, allobarbital and diphenylhydantoin. The results obtained show that the hydroxylamine derivatives of barbituric acid HB-2 (2-hydroxylamino-5-ethyl-5-propylbarbituric acid) and HB-7 (2-hydroxylamino-5-ethyl-5 sec. pentylbarbituric acid) have the most pronounced anticonvulsive activity, which suggests the considerable importance of the participation of GABA-ergic transmission in the realization of this activity.