Ethanol enhances recurrent inhibition in the dentate gyrus of the hippocampus

Intraperitoneal injection of ethanol (2 g/kg) substantially augmented recurrent inhibition in the dentate gyrus, as measured by population responses to paired-pulse stimulation of the perforant path. In contrast, this dose of ethanol had no significant effect on singly evoked (or conditioning) population spikes. These data indicate that the increased recurrent inhibition by ethanol was not due to a generalized depressant effect, and suggests that at these doses and time points ethanol can selectively alter synaptic transmission in the hippocampus.