Involvement of the caudal granular insular cortex in alcohol self-administration in rats.

Animal models of substance abuse have established a role for the caudal granular insular cortex (CGIC) in drug taking behaviour for several addictive substances, yet nothing has thus far been reported for alcohol. The current research was undertaken to examine the involvement of the CGIC in a rat model of alcohol self-administration. We investigated the inactivating effects of local infusions of a γ-aminobutyric acid agonist mixture (baclofen/muscimol) into the CGIC on alcohol self-administration under a fixed ratio-3 (FR-3). This inactivation of the CGIC decreased operant responding for alcohol along with a corresponding decrease in oral alcohol intake. Our results demonstrate the involvement of the CGIC in alcohol taking behaviour and suggest future studies examine the differential involvement of the various subregions of the insular cortex in various aspects of alcohol consumption.