Nitrous oxide inhibits auditory and visual responses of granule cells in the cerebellum.

Much of the laboratory investigation on the auditory and visual areas of the posterior vermis has been carried out under barbiturate anesthesia. It is now known that barbiturates potentiate GABA inhibition by binding directly to the GABA receptor protein. Since GABAergic receptors are present in many cell types of the cerebellar cortex, barbiturate anesthesia is likely to interfere severely with cerebellar physiology. We have examined auditory and visual responses in granule cells in the cerebellum of the cat under nitrous oxide anesthesia. To our surprise, nitrous oxide abolished auditory as well as visual responses in the granule cell layer in the posterior vermis. However, both auditory and visual responses recovered after the cessation of nitrous oxide.