The nucleus accumbens (NAc) plays a critical role in amphetamine-produced conditioned place preference (CPP). In previous studies, NAc basal and amphetamine-produced DA transmission was altered by Group II mGluR agents. We tested whether NAc amphetamine CPP depends on Group II mGluR transmission.NAc injections (0.5 microl/side) of the Group II mGluR antagonist (2 S)-a-ethylglutamic acid (EGLU: 0.01-0.8 microg but not 0.001 microg) impaired CPP. The drug did not block the acute locomotor effect of amphetamine.Results suggest that Group II mGluRs may be necessary for the establishment of NAc amphetamine-produced CPP. These receptors may also mediate other forms of reward-related learning dependent on this structure.