Figure 6.

Mice with selective deletion of Ca_v1.2 in D1R-expressing cells have a deficit in extinction of cocaine CPP and lower levels of CaMKIIα and P-GluA1 S831, but not total GluA1 at the hippocampal PSD. A, CaMK2^cre, Ca_v1.2^+/+ mice and CaMK2^cre, Ca_v1.2^fl/fl mice displayed similar acquisition and extinction of cocaine CPP. ***p < 0.001 compared with baseline; #p < 0.05, ###p < 0.001 compared with acquisition. B, Validation of the D1^cre, Ca_v1.2^fl/fl mouse line. Ca_v1.2 protein levels in hippocampal and NAc PSD fractions were significantly lower in D1^cre, Ca_v1.2^fl/fl mice compared with D1^cre, Ca_v1.2^+/+ mice. **p < 0.01. C, Compared with D1^cre, Ca_v1.2^+/+ mice, D1^cre, Ca_v1.2^fl/fl mice displayed similar acquisition of cocaine CPP, but demonstrated a deficit in extinction of cocaine CPP. ***p < 0.001 compared with baseline test; ###p < 0.001 compared with acquisition test. D, After cocaine CPP extinction test, D1^cre, Ca_v1.2^fl/fl mice had significantly lower protein levels of CaMKIIα and P-GluA1 S831 in the PSD-enriched fraction of the hippocampus compared with D1^cre, Ca_v1.2^+/+ mice, with no difference in GluA1 levels. ***p < 0.001. E, After the cocaine CPP extinction test, there were no significant changes in the proteins examined in NAc PSD fractions of D1^cre, Ca_v1.2^fl/fl mice compared with D1^cre, Ca_v1.2^+/+ mice. Data are presented as mean ± SEM.