[GABAergic mechanisms of the function of hippocampal-reticulo-neocortical system structures of the brain under thiopental anesthesia].

In experiments on rabbits with electrodes chronically implanted in the brain structures thiopental exhibited properties of a pronounced GABA receptor agonist. Muscimol potentiated the suppressive effect of the general anesthetic agent on electrographic and behavioral correlates of excitability of the periaqueductal gray matter, mesencephalic reticular formation and especially dorsal hippocampus and frontal neocortex. On the contrary, bicuculline reduced the anesthetic effect of thiopental but potentiated the inhibitory action of the cortex and hippocampus on the midbrain formations as compared with the effects of the barbiturate proper.