hM<sub>3</sub>D(G<sub>q</sub>)-mCherry is expressed on VTA to Acb neurons.

<p>Depicted in the upper row are single section images of (A) hM<sub>3</sub>D(G<sub>q</sub>)-mCherry expression, (B) Tyrosine hydroxylase (TH) expression and (C) combined hM<sub>3</sub>D(G<sub>q</sub>)-mCherry and TH expression. hM<sub>3</sub>D(G<sub>q</sub>)-mCherry expression is restricted to the ventral tegmental area (VTA), as no mCherry expression could be observed in the substantia nigra pars compacta (SNpc) or surrounding areas. Depicted in the lower are single section confocal images of (D) hM<sub>3</sub>D(G<sub>q</sub>)-mCherry expression, (E) TH expression and (F) combined expression of hM<sub>3</sub>D(G<sub>q</sub>)-mCherry and TH. Two populations of hM<sub>3</sub>D(G<sub>q</sub>)-mCherry expressing VTA to nucleus accumbens (Acb) projection neurons can be distinguished, one population that does not express TH (vertical white arrows) and one population that does express TH (horizontal yellow arrows).</p>