Recovery of social interaction deficits by acute treatment with 7,8-DHF in VRK3-KO mice. (A and B) Sociability and preference for social novelty at 1 d (test 1) after acute treatment with 7,8-DHF or vehicle; sociability with mouse 1 (blank bar) versus object (filled bar; A: n = 7, 8 and 8, 9 for WT and VRK3-KO mice; WT vs. VRK3 KO F1,56 = 49.99, P < 0.0001, interaction F3,56 = 3.61, P = 0.0186, two-way ANOVA; ***, P < 0.001; **, P < 0.01; Bonferroni’s post-test) and preference for social novelty with familiar mouse (blank bar) versus novel mouse (filled bar; B: WT vs. VRK3 KO F1,56 = 22.17, P < 0.0001, interaction F3,56 = 4.58, P = 0.0069, two-way ANOVA; ***, P < 0.001; **, P < 0.01; *, P < 0.05; Bonferroni’s post-test). (C and D) Sociability and preference for social novelty at 7 d (test 2) after acute treatment with 7,8-DHF or vehicle, sociability (C: n = 7 and 8, 9 for WT and VRK3-KO mice; WT vs. VRK3 KO F1,42 = 10.01, P = 0.0029, interaction F2,42 = 4.55, P = 0.0163, two-way ANOVA; ***, P < 0.001, Bonferroni’s post-test), and preference for social novelty (D: WT vs. VRK3 KO F1,42= 4.13, P = 0.0487, two-way ANOVA; *, P < 0.05, Bonferroni’s post-test). n.s., not significant. All values represent mean ± SEM.