Potentiation of N-methyl-D-aspartate receptor-dependent afterdischarges in rat dentate gyrus following in vitro ethanol withdrawal.

The contribution of NMDA receptors to neuronal hyperexcitability following in vitro ethanol withdrawal was examined using afterdischarges (ADs) in rat dentate gyrus as a model system. ADs were evoked by high frequency stimuli and blocked by N-methyl-D-aspartate (NMDA) receptor antagonists. Ethanol (75 mM) inhibited ADs, and following in vitro ethanol withdrawal, the duration of afterdischarges was significantly enhanced (37 +/- 2%, n = 21). Therefore, in vitro ethanol exposure with subsequent withdrawal is associated with an enhancement of NMDA receptor-dependent afterdischarges. These results are consistent with the involvement of NMDA receptors in ethanol withdrawal hyperexcitability.