Anandamide (AEA), THC, and AM404 priming-induced reinstatement of extinguished drug seeking behavior in anandamide-, THC- and cocaine-experienced monkeys. Priming i.v. injection with THC (0.04 mg/kg), anandamide (0.3 mg/kg), or AM404 (0.03–0.3 mg/kg) reinstated extinguished self-administration behavior in anandamide- (a; n=4), THC- (b; n=5), and cocaine-trained (c; n=4) monkeys. Pretreatment with rimonabant (0.3 mg/kg) blocked the reinstatement induced by priming injection of AM404 (0.3 mg/kg) in all three groups of monkeys. Number of vehicle injections self-administered during 1-h sessions are shown. Bars represent means ± SEM. “Vehicle” bars represent the average of 4–6 extinction sessions prior to the test sessions. *p < 0.05, **p < 0.01, post-hoc comparisons with “Vehicle” condition; ##p < 0.01, post-hoc comparisons with “AM404 0.3” condition; Tukey test.