NaB can ameliorate thermal hyperalgesia and working memory impairment, but not mechanical allodynia in CCI mice. a: protocol for the experiment. b: OFT (two-way ANOVA: interaction, F(1, 36) = 1.558, p = 0.22; CCI, F(1,36) = 0.1764, p = 0.6769; NaB, F(1,36) = 3.672, p = 0.0633). c: PWT (two-way ANOVA: interaction, F(1, 36) = 1.334, p = 0.2558; CCI, F(1,36) = 74.81, p < 0.0001; NaB, F(1,36) = 0.2134, p = 0.6469). d: PWL (two-way ANOVA: interaction, F(1, 36) = 4.920, p = 0.033; CCI, F(1,36) = 52.77, p < 0.0001; NaB, F(1,36) = 4.92, p = 0.033). e. Number of arm entries in Y-maze (two-way ANOVA: interaction, F (1, 36) = 3.312, p = 0.0771; CCI, F (1,36) = 0.7431, p = 0.3944; NaB, F (1,36) = 0.2294, p = 0.6349). f: spontaneous alternation in the Y-maze (two-way ANOVA: interaction, F (1, 36) = 8.414, p = 0.0063; CCI, F(1,36) = 0.8044, p = 0.3757; NaB, F(1,36) = 0.005, p = 0.94). g: BDNF levels in hippocampus (two-way ANOVA: interaction, F(1, 36) = 2.121, p = 0.1540; CCI, F(1,36) = 1.248, p = 0.2714; NaB, F(1,36) = 4.503, p = 0.0408). h: HDAC2 levels in hippocampus (two-way ANOVA: interaction, F(1, 36) = 0.9466, p = 0.3371; CCI, F(1,36) = 3.881, p = 0.0566; NaB, F(1,36) = 5.593, p = 0.0235). N = 10/group. *p < 0.05; **p < 0.01; ***p < 0.001. PWT, paw withdrawal threshold; PWL, paw withdrawal latency; OFT, open field test; CCI, chronic constriction injury; NaB, sodium butyrate.