Figure 5.

Elevated operant responding for low-dose cocaine and drug-paired cues during extinction in cKO mice. (A) Nosepoke response of food-trained mice implanted with indwelling intravenous catheters and allowed to nosepoke for cocaine infusions (controls, n = 7; cKO, n = 7). (B) Total dose self-administered at the different cocaine concentrations in (A). (C) Cocaine seeking, i.e., responding for light and sound cues previously associated with cocaine in the absence of the drug, of mice from A that had been responding for 0.75 mg/kg per infusion (inf) and subsequently subjected to 21 d of forced cocaine abstinence (controls, n = 6; cKO, n = 5). Group data represent mean ± SEM. *p < 0.05; **p < 0.01 versus Ctrl. Reprinted from Alsiö et al., 2011 [61].