Effect of systemic ethanol on basal and stimulated glutamate releases in the nucleus accumbens of freely moving Sprague-Dawley rats: a microdialysis study

This study was conducted to assess the impact of systemic ethanol (EOH) on the glutamatergic transmission in the nucleus accumbens (NACC). Extracellul ar concentrations of glutamate (GLU) in the NACC of freely moving Sprague-D awley rats were monitored by intracerebral microdialysis. Intraperitoneal i njection of EOH at a dose of 2 g/kg significantly decreased basal extracell ular GLU by 21%. In addition, administration of the same dose of EOH signif icantly attenuated 150 mM K+-stimulated GLU release from the NACC by more t han 50%. Since K+-stimulated GLU release has been demonstrated to derive la rgely from nerve terminal depolarization, reductions of K+-evoked GLU relea se may reflect in part the effect of EOH on the neurotransmitter pool. The present results suggest that EOH may suppress glutamatergic transmission in the NACC by lowering presynaptic GLU release. (C) 1998 Elsevier Science Ir eland Ltd. All rights reserved.