Fig 4.
Time course of extracellular NAc dopamine efflux in response to cocaine in M4−/− (white) and M4+/+ (black) mice, n=4-7. Cocaine 30 mg/kg (circle) significantly increased extracellular dopamine in M4−/− mice (samples 20 min to 140 min, p<0.001). This response was significantly enhanced in M4−/− mice compared to M4+/+ mice (***p<0.001, **p<0.01 and *p<0.05). Figure 4. Insert shows cocaine induced dopamine efflux as AUC from 20-80 min. Both genotypes; M4−/− and M4+/+ mice show both a significant dose- and genotype-dependent increase in dopamine efflux (***p<0.001 and **p<0.01).