Average number of responses during the 7-day period of reacquisition of ethanol-reinforced responding (left panel) for Experiment 1. These rats previously received injections of saline (filled circles), 1.25 mg/kg yohimbine (open circles), or 10 mg/kg propranolol (open squares) following 45 min extinction sessions. The home-cage group (filled diamonds) is also shown. In the right panel, the average number of responses for all 7 days of ethanol self-administration sessions is shown for the same groups (saline = solid black bar, 1.25 mg/kg yohimbine = lined bar, 10 mg/kg propranolol = solid white bar, home-cage rats = cross-hatched bar). Data for all groups (n=7) are shown as means ± SEM.