Ifenprodil (2.5 μg/μl/side), PP2 (1.5 ng/μl/side), or vehicle was infused 15 min before the beginning of the test session. A, Mean ± SEM of the number of presses during a 30-min test in extinction. n = 7. B, Mean ± SEM of latency in seconds to the third press (first reward) during the final extinction session and the reinstatement test. C, Mean ± SEM of the number of presses during the final extinction session and reinstatement of ethanol-seeking induced by an oral ethanol prime. B-C, n = 8. #P < 0.05, ##P < 0.01, ###P < 0.001 vs. extinction *P < 0.05, **P < 0.01, treatment vs. vehicle.