Figure 2.
The effects of s.c. nalmefene on responses to alcohol and alcohol consumed in g kg‐1 body weight (30‐min session). Nalmefene was administered for four consecutive days with a washout period of 2 days between doses (Latin square design). According to its peak plasma concentration, nalmefene was injected s.c. 20 min before the operant alcohol self‐administration session (control group, n = 16; nalmefene groups, n = 24). (A, C) Data represent the mean ± SEM of the accumulated or day by day alcohol responses to 10% v·v−1 alcohol, and (B, D) represent their corresponding g alcohol consumed kg‐1 body weight. ** P < 0.01, *** P < 0.001 compared with the vehicle group; ## P < 0.01, ### P < 0.001 compared with the lowest dose of nalmefene. There were no significant differences throughout the withdrawal of nalmefene (washout period).