Excessive cocaine use results from decreased phasic dopamine signaling in the striatum

The authors measured striatal dopamine (DA) release in vivo using fast-scan cyclic voltammetry in a model involving escalating self-administration of cocaine in rats. Phasic DA release in ventromedial striatum was negatively correlated with escalation of cocaine intake. The DA precursor L-DOPA restored phasic DA release and reversed escalation of cocaine intake.