DESCRIPTION (provided by applicant): The focus of this research proposal is to examine the role of GABA in adolescent anabolic steroid induced aggression. The GABAergic neural system is implicated in the control of aggression yet the role of GABA neurotransmission in this behavior is unclear. Exposure to AAS has been shown to increase aggression in hamsters and it is possible that exposure during adolescence alters the normal development of the GABA system. The GABAergic neural system is of particular interest in this paradigm because it has been shown that steroids directly interact with GABAA receptors in brain. Recent data shows that adolescent AAS exposure results in alterations in GAD65-ir in primary aggression areas in hamster brain and correlates with increased aggression. The goals of the experiments outlined in this proposal are 1) to manipulate adolescent AAS-induced aggression by pharmacologically targeting the GABAA receptor and 2) to examine how adolescent AAS exposure can alter the activity and/or expression of the GABA system to provide a more complete model of the circuitry involved in AAS-induced aggression. These studies will provide a better understanding of GABA's role in the neural and behavioral effects of adolescent steroid abuse.