Enhanced locomotor responses to acute cocaine in DKO mice. A–C, Mice were habituated to the testing chamber for 60 min before injection with 10 mg/kg cocaine injected intraperitoneally at time 0. Ambulatory distance traveled is shown for AC1−/−, AC8−/−, DKO, and WT (AC1+/+) mice. D, Ambulatory distance traveled over the first 30 min after injection for saline and three doses of cocaine in WT and DKO mice. n = 9–15 mice per group. Two-way ANOVA, **p < 0.01 (Tukey's post hoc test).