Figure 5. Both NPAS2 and SIRT1 regulate cocaine preference through their expression in the NAc.

(A) C57BL/6J mice were injected bilaterally into the NAc with either AAV2-Npas2-shRNA-GFP or scramble control, while Npas2 mutant or wild-type mice were injected with either AAV2-CMV-eGFP-2A-Sirt1 or eGFP control. The inset box depicts a representative image of virus placement and spread, as measured by GFP immunofluorescence. AC indicates anterior commissure, while arrow indicates virus injection path. (B) Following two weeks of recovery, C57BL/6J mice injected with either Npas2-shRNA or scramble were conditioned to saline or cocaine (5 mg/kg) and injected with vehicle or resveratrol (20 mg/kg, i.p.) 30 minutes before conditioning. Viral-mediated knock-down of Npas2 in the NAc attenuates resveratrol mediated increases in cocaine CPP – with both main effects of virus and treatment measured by a 2-way ANOVA. Expanding on the simple main effects, resveratrol significantly increased cocaine CPP in the scramble group (*, p<0.05), but not in the Npas2-shRNA group (n.s., p=0.5094). (C) Npas2 mutant mice overexpressing Sirt1 in the NAc conditioned to saline and cocaine (5 mg/kg) show an attenuated preference for cocaine in the CPP task relative to controls – with both a main effect of genotype and a trending effect of virus measured by a 2-way ANOVA (@, p=0.0512). Expanding on the simple main effects, Sirt1 overexpression increased cocaine CPP in the WT group (#, p=0.0943), but not in the Npas2 MUT group (n.s., p=0.2691). Horizontal or vertical bars indicate main effect comparisons. Symbols above plotted bars indicate within group statistical comparisons. Throughout, asterisks indicate significance (* p<0.05, ** p<0.01). Data represented as Mean ± SEM (n= 10–15).