Effects of 10 Hz ILCx stimulation on active responding during nicotine self-administration and on cue-induced reinstatement. A, Timeline of experiment. Rats were: (1) trained for nicotine self-administration (60 d), (2) anesthetized, received ILCx electrical stimulation 24 h after the last session (1 d) and CB1 antagonist pretreatment (Veh or AM251, 400 μm; 60 nl), (3) tested for nicotine taking (4 d), (4) trained for extinction (2 d), and (5) tested for cue-induced nicotine seeking. Effects of ILCx and sham stimulation in vehicle and AM251-treated rats on the following: B, Total number of visits in active hole during the whole session. C, Total nicotine intake over the whole session. D, Total number of visits in active hole during time-out. E, Total number of visits in the active hole during the cue-induced reinstatement period. Post hoc active hole Veh Session 1 versus Session 2 and Veh Session 1 versus Session 3, **p < 0.01. ^@@p < 0.01, main effect stimulation versus sham stimulation. ⁺⁺p < 0.02. B–D, Data are mean ± SEM. E, Data are mean + SEM.