Figure 5.
Molecular characterization of conditional D1R- and D2R-γ7 KO mice. AC activity in striatal membranes of male and female Gng7fl/flD1Cre+ (A,B,E,F), Gng7fl/flD2Cre+ mice (C,D,G,H), and WT littermates. AC activity was measured under basal conditions (DMSO) or in the presence of 10 μm FSK, 25 μm D1R agonist SKF 83822, or 25 μm A2AR agonist CGS 21680. AC stimulation by FSK was not significantly different between D1R- or D2R-γ7 KO mice and WT controls (A–D, two-way repeated-measures ANOVA: ***p < 0.001 basal vs FSK, “treatment” effect). In male and female Gng7fl/flD1Cre+ mice, D1R agonist SKF 83822 did not significantly elevate cAMP levels over the baseline level (E,F, two-way repeated-measures ANOVA and Tukey's post hoc: *p < 0.05, **p < 0.01, Gng7fl/fl-basal vs Gng7fl/fl-SKF 83822; ##p < 0.01, Gng7fl/flD1Cre+ vs Gng7fl/fl, “genotype × treatment” effect). Membranes incubation with A2AR agonist CGS21680 caused a significant increase of cAMP levels in both genotypes and sexes (E,F, two-way repeated-measures ANOVA and Tukey's post hoc: +++p < 0.001, CGS 21680 vs basal, “treatment” effect). In contrast, AC stimulation with SKF 83822 was preserved in male and female Gng7fl/flD2Cre+ mice compared with controls (G,H, two-way repeated-measures ANOVA: **p < 0.01, ***p < 0.001, SKF 83822 vs basal, “treatment” effect; #p < 0.05, Gng7fl/flD2Cre+ vs Gng7fl/fl, “genotype” effect), while AC stimulation with CGS 21680 was selectively impaired in the conditional KO line (G,H, two-way repeated-measures ANOVA and Tukey's post hoc: ++p < 0.01, +++p < 0.001, Gng7fl/fl-basal vs Gng7fl/fl-CGS 21680; $$p < 0.01, Gng7fl/flD2Cre+-CGS21680 vs Gng7fl/fl-CGS21680, “genotype × treatment” effect). Data are mean ± SEM. n = 5 mice/group.