Electrophysiologic effects of acute ethanol exposure. I. Alterations in the action potentials of dorsal root ganglia neurons in dissociated culture.

ABSTRACT

Dissociated dorsal root ganglion neurons from embryonic rats were exposed to 0.05, 0.15 and 0.30 g% ethanol for 1 h. Action potentials were recorded and statistically compared for differences from the control values. Exposure to ethanol produced no significant alterations in the resting membrane potential, spike amplitude, or maximum rate of rise in any of the experimental conditions. Significant differences were noted in parameters associated with the repolarization phase including decreases in the maximum rate of fall and one-half time to convergence and increases in the full width of half maximum and full width of base parameters. These alterations were reversed within 30 min after ethanol removal. In order to determine the specific ionic conductances affected by ethanol, action potentials were recorded from neurons exposed to specific Na+, Ca2+, and K+ current blockers. Analysis of the data indicates that K+ conductance is decreased as a result of a decreased Ca2+ current. Further, maximum Na+ conductance is not significantly affected by physiologic concentrations of ethanol.