Schematic of placement site and viral construct and image of viral transfection (GFP in NAc) (A). Timeline of experiment. We took baseline sucrose preference levels from all mice before stress exposure. All females were exposed to social defeat and then one week later, viral vectors (GFP or Rgs2) were microinjected into the NAc core. Four days later, stressed mice received a sucrose preference test followed by a social interaction test (B). Neurotrace staining shows that GFP expression occurs in neurons and western blot analysis demonstrates that HSV-RGS2 vectors increase RGS2 protein in the NAc (C). Rgs2 overexpression reversed anhedonia-like phenotypes in the sucrose preference test (D). Rgs2 overexpression increased social approach (E) and decreased social vigilance (F) when the target was present but not while the target was absent (G, H). Rgs2 overexpression did not alter distance traveled (I) or center time (J) during the open field phase. * p<0.05 planned comparison v. GFP. **p<0.01 planned comparison v. GFP. ***p<0.001 planned comparison v. GFP. †p<0.05 paired t-test with baseline (before stress). †††p<0.001 paired t-test with baseline (before stress). Group N’s: RGS2: 7, GFP: 6, miss: 4. Scale bar in 4A=200μM. Scale bar in 4C=25μM.