Cocaine is a highly addictive drug with severe detrimental physical and mental health effects. Important features of addiction are loss of control over drug use and increased expenditure of time and energy directed toward attaining and using the drug of abuse (Roberts et al., 2007; for review see Koob, 2009). Cocaine addicts lose their ability to control their cocaine intake, and in the process of gaining access to cocaine they will sacrifice their health and social lives (Dackis and O'Brien, 2001). Recent research has significantly improved our understanding of cocaine's mechanisms of action. Cocaine is known to increase dopamine (DA) levels in the shell of the nucleus accumbens (NAc) to levels several fold higher than the increase in dopamine seen in response to natural rewards. Cocaine does this by blocking DA transporter (DAT)-mediated reuptake of DA (Huang et al, 2009, Carboni et al, 2001, Pettit and Justice, 1989). This increase in dopamine, which lingers in the synaptic cleft making it more accessible to both pre- and post-synaptic receptors, partly accounts for the euphoric and addictive properties of cocaine (for review
