A, Effects of NAc shell infusions of DHK on cue-induced cocaine-seeking behavior. Cue-induced cocaine seeking was significantly attenuated in the ceftriaxone-treated, saline-infused and ceftriaxone-treated, DHK-infused cocaine-seeking groups compared with the saline-treated and saline-infused cocaine-seeking groups (***p < 0.0001). No differences were detected between ceftriaxone-treated, DHK-infused rats and the ceftriaxone-treated, saline-infused rats (p = 0.9715). Note that cue-induced cocaine seeking was assessed in extinction test sessions in which lever presses led to contingent cue presentations but not cocaine. B, Illustration of cannula tips in NAc shell. Sections are presented +2.7 mm anterior to bregma.