Interestingly, although chronic exposure to ethanol vapor augments GABA release in the CeA, there does not appear to be any tolerance to the effect of acute ethanol following chronic ethanol inhalation. Roberto and colleagues [52] confirmed their previous findings that medium doses of acute EtOH (22 and 44mM) increase the amplitude of evoked IPSCs and IPSPs in slices from both ethanol-treated and naïve rats. Basal GABAergic transmission appears to be enhanced following chronic ethanol, as IPSCs are larger on average in slices from ethanol treated animals. However, 44mM EtOH enhances evoked GABAergic responses to a similar extent in ethanol-treated and naïve rats (150% of control), and paired pulse ratios are similarly reduced by acute ethanol application in slices from both groups.
