Figure 1.

A_2AR-CB₁R heteromers are located on GABAergic neurons rather than glutamatergic projections in the mouse dorsal striatum. (a, b) PLA assays were performed in dorsal-striatum sections from 3–4-month-old mice of different genotypes. A_2AR-CB₁R heteromers are shown as green dots. Nuclei are colored in blue by DAPI staining. (a) Representative low-magnification image of tissue sections used for PLA assays. Left, DAPI-stained field; right, bright field. Scale bar: 1 mm. Representative pictures from control CB₁R-floxed, GABA-CB₁R^−/−, Glu-CB₁R^−/−, and GABA-Glu-CB₁R^−/− mice. Scale bar: 20 μm. (b) Representative pictures from Stop-CB₁R, GABA-CB₁R-RS mice, Glu-CB₁R-RS mice and CB₁R-RS mice. Scale bar: 20 μm. (c) Quantification of the number of cells containing one or more dots expressed as the percentage of the total number of cells (blue nuclei). Data are the mean±SEM of counts in 5–14 different fields from three different animals of each type. One-way ANOVA followed by Dunnet post hoc test showed a significant (*p<0.05, ***p<0.001) decrease of heteromer expression compared to control CB₁R-floxed mice (a) or to CB₁R-RS mice (b). Further details of statistical analyses are given in Supplementary Table S2.