Figure 2.

Mean (+SEM) time spent in the cocaine-paired chamber during conditioned place preference testing by session for sedentary and exercise rats. Exercise and sedentary rats formed a significant preference for cocaine, as measured by an increase in time spent in the paired chamber from pretest to test (*p<0.05). Both treatment groups also showed extinction of this preference, as measured by a decrease in preference from test day (^p<0.05) and no change from pretest day (p>0.05). Sedentary rats exhibited stress-induced reinstatement of preference, as measured by an increase in time spent in the paired chamber from pretest (*p<0.05) and extinction (+p<0.05) to the stress reinstatement session, and no difference between test and stress reinstatement (p>0.05). Exercise inhibited stress-induced reinstatement, such that there was no difference between pretest or extinction and the stress reinstatement session (p>0.05), and there was a decrease in preference from test day (p=0.067). *p<0.05 vs. pretest, +p<0.05 vs. extinction, ^p<0.05 vs. test