Fig. 1

Effect of different dosages of MPL pre-injection on CSDS-induced anxiety-like behaviors in mice. A Timeline for the evaluation of the preventive effect of a single MPL pre-injection on CSDS-induced anxiety-like behaviors in mice. B‒D Quantitative analysis showing the effect of a single MPL injection (200, 400, and 800 μg/kg) 1 day before stress exposure on the time spent in open arms (B), the number of entries into open arms (C), and the number of entries into total arms (D) in the EPM test in mice treated with or without CSDS and/or MPL (n = 10, **p < 0.01 vs. vehicle; ##p < 0.01 vs. vehicle + CSDS). E, F Quantitative analysis showing the effect of the single MPL injection (200, 400, and 800 μg/kg) 1 day before stress exposure on the time spent in lit side (E) and the number of total transitions in both lit and dark side (F) in the LDT in mice treated with or without CSDS and/or MPL (n = 10, **p < 0.01 vs. vehicle; ##p < 0.01 vs. vehicle + CSDS). G, H Quantitative analysis showing the effect of the single MPL injection (200, 400, and 800 μg/kg) 1 day before stress exposure on the time spent in the center region of the open field (G) and the total distance (H) in the OFT in mice treated with or without CSDS and/or MPL (n = 10, **p < 0.01 vs. vehicle; ##p < 0.01 vs. vehicle + CSDS). Data are shown as mean ± SEM. Comparisons were made by two-way ANOVA with (B, C, E, G) or without (D, F, H) Bonferroni test