[GABA-ergic mechanisms of the cerebrovascular effects of fenazepam and diazepam].

Under GABA-receptor blockade bicuculline prevented or substantially reduced the depressant effects of phenazepam and diazepam on the nerve control of cerebral circulation. Simultaneously, the depressant effects of the drugs on tonic activity and reflex responses in the sympathetic nerves were substantially decreased. Bilateral antagonism between phenazepam and diazepam, on the one hand, and bicuculline, on the other, was found. The data obtained indicate the contribution of GABA-ergic mechanisms to the development of phenazepam and diazepam cerebrovascular effects.