The current study provides evidence that the GABAAR α4 subunit in the NAc shell is required for the reinforcing properties of self-administered ethanol. We found that viral-mediated reductions in the expression of the GABAAR α4 subunit in the NAc shell, but not core, reduced lever-press responding for ethanol, but not sucrose. These effects were not apparent at the initiation of the session, indicating that α4 knockdown did not reduce ethanol seeking. Together with our previous results in which α4 reductions in the NAc shell were found to reduce ethanol intake and preference when offered in bottles on the home cage (Rewal et al. 2009), our findings support a critical role for GABAAR α4-containing receptors in the reinforcing effects of orally administered ethanol at the moderate concentrations commonly attained during social drinking.
