An EEG investigation on the role of cerebello-rubral system in the effects of diazepam and pentobarbital.

The EEG effects of diazepam and pentobarbital at the level of cerebello-rubral pathways (i.e., cerebellar cortex, interposed, fastigial and red nuclei) were studied. The drugs elicited a slowing of frequency and an enhancement of the voltage of the waves at the level of cerebellar and red nucleus leads. The effect was antagonized by picrotoxin or pentamethylenetetrazole, while ethyl - 8 - fluoro - 5,6 - dihydro - methyl-6-oxo-4H-imidazol [1,5 a][1,4]benzodiazepin-3-carboxylate (Ro 15-1788) antagonized only the effect of diazepam. The relationships between the EEG alterations and the behavioural effects of diazepam and pentobarbital, which are endowed with muscle relaxing, sedative-anesthetic and anticonvulsant activity, are discussed.