Electrophysiology of nitrous oxide on cerebellar granule cells: a single-cell study.

ABSTRACT

We recorded 18 single cells in the granule cell layer of the cat. Each single cell was screened and identified as a granule cell based on a set of criteria derived from known electrophysiological properties of granule cells. We then monitored the effects of nitrous oxide on the spontaneous activities and the auditory responses of these cells. Nitrous oxide consistently caused a severe inhibition of spontaneous activities as well as responses to sound in these cells. Furthermore, the amplitudes of their action potentials decreased during the inhibition. Three of the 18 cells were subsequently injected intracellularly with HRP. All three were verified to be granule cells. In those granule cells we recorded intracellularly, nitrous oxide did not change the resting membrane potentials. The gradual decrease in the amplitudes of action potentials suggested that some of the mechanisms leading to the genesis of action potentials were being altered by nitrous oxide. It is also possible that nitrous oxide may act on synaptic transmission at a site located postsynaptically on the granule cells.