AbstractBackgroundAlcohol abuse and dependence are a serious public health problem. A large number of alcohol‐regulated genes, (ARGs) are known to be influenced by alcohol use and withdrawal (AW), and recent evidence suggests that neuroadaptation to alcohol may be due in part to epigenetic changes in the expression ofARGs.Gabra4,which encodes theα4 subunit ofGABAAreceptors (GABAARs), is one of a number ofARGs that show remarkable plasticity in response to alcohol, being rapidly upregulated by acute alcohol exposure. This study addressed the effects ofAWon changes in the expression ofGabra4and related genes that encode other subunits ofGABAARs, and the potential regulation ofGabra4by microRNAs.MethodsWe studied gene and microRNAs expression, usingRT‐PCRand microRNAmicroarray in cultured cortical neurons treated with alcohol, which was then removed in order to simulateAWin vitro. We also used microRNAmimics or inhibitors, and a promoter‐reporter construct carrying the 3′UTRofGabra4.ResultsEleven hours after removal of alcohol,Gabra4was downregulated,with a modest increase in the expression ofGabrg2,but no change in the expression ofGabra1, Gabrd,orGabrb2. microRNAprofiling in neurons undergoingAWrevealed upregulation in the expression of miR‐155, miR‐186, miR‐24, and miR‐375 after 8 h ofAW. Transfection with molecular mimics of miR‐186, miR‐24, or miR‐375 also downregulatedGabra4expression, whereas transfection with the corresponding inhibitors of these microRNAs normalizedGabra4expression inAWneurons to the level measured in control neurons. Promoter‐reporter experiments supported the idea that miR‐155, miR‐186, miR‐24, miR‐27b, or miR‐375 bind to the 3′UTRofGabra4and thereby inhibit protein production.ConclusionsOur data suggest thatAWdecreasesGabra4expression, and that this may be mediated in part by the induction of specific microRNAs in cortical neurons duringAW.