Comparison of the significant BP categories between the ACB-shell and CeA indicated that only 9 of the 34–38 different categories were in common, supporting the idea of region-dependent ethanol effects on gene expression. Furthermore, in some of the BP categories that were similar between the 2 regions, there were few genes in common within these categories. For example, in the synaptic transmission category (Table 2), only two genes (Gria1, Syt10) were in common between the 2 regions. In the ‘neurite development’ category, only one gene (Mtap2) was in common between the 2 regions (Table 2). The observation that different genes were altered within similar categories suggests that similar alterations in neuronal functions may be occurring in both regions, but the actions of ethanol on altering synaptic transmission and neurite development may be occurring by different mechanisms in the two regions. The higher proportion of genes that had increased expression compared to decreased expression in the synaptic transmission and neurite development categories (Table 2) suggest that changes may be taking place that enhance neuronal function, and, possibly, synaptic plasticity.
