
Fig. 4 Effects of SCH 23390 (0.25 mg/kg) and raclopride (0.4 mg/kg) on cocaine (15 mg/kg)-induced locomotor, CART expression, cAMP levels, PKA activity, and pCREB levels in the mice striatum. (A) Cocaine was administered in mice one time per day for 5 days. The locomotor activity was measured using the tilting-type ambulometer. (B) The cAMP levels were measured using the competition enzyme-linked immunoassay (ELISA). (C) After PKA was purified by immunoprecipitation, the PKA activity was measured using a radiometric assay. The CART levels (D), CREB phosphorylation (E), and (F) CREB levels were observed using western blotting. A quantitative analysis was conducted by measuring the relative OD of the immunoreactive signal for preproCART, pCREB, CREB, and GAPDH. Data represent the means±SEM of 4 mice. The total twenty mice were used. **p<0.01 and ***p<0.001, compared with that of the control (saline) group; ##p<0.01 and ###p<0.001, compared with that of the cocaine group; +p<0.001 and +++p<0.001, compared with that of the raclopride group.

Fig. 5 Effects in WT mice and D1R-KO mice treated with cocaine (15 mg/kg) on the 5th day on locomotor activity (A), cAMP levels (B), PKA activity (C), CART levels (D), pCREB levels (E), CREB levels (F). A quantitative analysis was conducted by measuring the relative OD of the immunoreactive signal for preproCART, pCREB, CREB, and GAPDH. Data are given as the means±SEM of 4~5 mice. The total twenty mice were used. **p<0.01 and ***p<0.001, compared with that of the control (saline) group; #p<0.05, ##p<0.01 and ###p<0.001, compared with that of the WT or KO mice group.

Fig. 6 Effects in WT mice and D2R-KO mice treated with cocaine (15 mg/kg) on the 5th day on locomotor activity (A), cAMP levels (B), PKA activity (C), CART levels (D), pCREB levels (E), CREB levels (F). Quantitative analysis was conducted by measuring the relative OD of the immunoreactive signal for prepro CART, pCREB, CREB, and GAPDH. Data represent the means±SEM of 3~4 mice. The total sixteen mice were used. *p<0.05, **p<0.01 and ***p<0.001, compared with that of the control (saline) group; #p<0.05, compared with that of the KO or WT mice.