Figure 8. RXRα overexpression in NAc mildly affects natural reward behaviors.

(A) Experimental design for behavioral testing, using male mice (n = 12-13/group).

(B) RXRα overexpression did not affect baseline locomotor activity (left, unpaired Welch’s t-test: t_22.392 = −1.3742, p = 0.1830) or anxiety-like behaviors (right, unpaired Welch’s t-test: t_22.916 = 1.1312, p = 0.2697) in the open-field test.

(C) RXRα overexpression did not alter social investigation behaviors towards either a male (left, unpaired Welch’s t-test: t_22.827 = −0.5106, p = 0.6145) or female (right, unpaired Welch’s t-test: t_22.475 = 0.6265, p = 0.5373) target. Dotted line represents a Social Interaction Ratio of 1.

(D) RXRα overexpression reduced the latency to feed in a novel anxiogenic context during NSF testing (unpaired Welch’s t-test: t_21.688 = 3.3708, p = 0.002796).

(E) RXRα overexpression did not affect open-arm exploration in the EPM test (unpaired Welch’s t-test: t_21.44 = 0.94804, p = 0.3537).

(F) RXRα overexpression induced a trend towards faster saccharine water Pavlovian learning of conditioned approach behavior (LMM-ANOVA: interaction Virus:Day: F_4,91 = 1.9778, p = 0.1045).

(G) RXRα overexpression induced a trend towards faster saccharine water instrumental learning of operant responding on FR1 schedule (left, LMM-ANOVA: main effect of Virus: F_1,22 = 3.0245, p = 0.09599), but had no effect on stable FR5 (middle, LMM-ANOVA: main effect of Virus: F_1,22 = 0.0011, p = 0.9734) or RR5 (right, LMM-ANOVA: main effect of Virus: F_1,21.98 = 0.0014, p = 0.9700) responding.

(H) RXRα overexpression induced a trend towards decreased motivation for saccharine water reward as measured by reduced PR breakpoint (unpaired Welch’s t-test: t_20.978 = 1.6453, p = 0.1148).

Bar graphs and line graphs represent mean ± SEM.