Fig. 5.

Effects of M100907 pretreatment on cocaine-primed reinstatement of extinguished cocaine-seeking behavior, expressed as mean responses/hour ± SEM on the active lever in each dosage group (a) and collapsed across dosage groups (b). Animals assigned to receive 0.1 (n=13), 0.3 (n=13), 1.0 (n=13), or 1.5 (n=14) μg/0.2 μl/side M100907 into the vmPFC were tested on 1 day with their assigned dose (striped bar) and on another day with the vehicle (black bar), with order counterbalanced. These pretreatments were infused immediately before the animals received the cocaine prime (10 mg/kg, i.p.) and were then immediately placed into the self-administration chambers. No cues were presented during the test sessions. Baselines (white bar) were calculated as the average number of active lever presses during the extinction sessions immediately preceding each test. When collapsed across doses (b), there was a significant increase in responding on both the vehicle and M100907 test days relative to extinction baseline and a significant decrease in responding on the M100907 test day relative to the vehicle test day. The star (★) represents a significant difference from extinction baseline, test of simple main effects, P<0.05. The plus sign (+) represents a significant difference from vehicle test day, test of simple main effects, P<0.05