Roberto and colleagues [51] have also found that medium doses of EtOH (22 and 44mM) increase GABAA–mediated IPSCs and IPSPs in most rat CeA neurons. Furthermore, 44mM EtOH increases the amplitude of evoked IPSPs and IPSCs. This effect was not altered by concurrent superfusion of a GABAB receptor antagonist (in contrast to findings in the hippocampus, nucleus accumbens, and basolateral amygdala). Ethanol decreased paired-pulse ratios (inter-event interval: 50ms) at 44mM, but not at lower concentrations (11 and 22mM). This medium EtOH dose also increased the frequency of sIPSC, and both the frequency and amplitude of mIPSCs, suggesting that ethanol increases inhibitory signaling in this brain region via pre- and post-synaptic mechanisms, with presynaptic effects more obvious at higher doses.
