The dopamine D3 partial agonist CJB090 was injected i.v. immediately before a methamphetamine (0.05mg/kg/injection) test session. Data on the top graph (A) correspond to test sessions under FR1 schedule of reinforcement and data on the bottom graph (B) are from sessions under a PR schedule. Sessions under a FR1 schedule lasted 1h and sessions under a PR schedule ended when rats failed to achieve methamphetamine reinforcement within 1h (see methods for details). Filled bars are methamphetamine extended access rats (6h/session daily, LgA, n=7) and stripped bars are methamphetamine limited access rats (1h/session every 2–3 days, ShA, n=6). Data are expressed as the mean ± SEM of the number of methamphetamine injections per session on the left axis (A and B) and methamphetamine intake in mg/kg (A) or ratio/injection (B) on the right axis. Different between access conditions: *p<0.05, ***p<0.001. Different to vehicle-injected rats in the same access condition: #p<0.05, ###p<0.001.