Fig. 7.

Microinjection of Y1 receptor agonist into the MHb alleviates GTN-induced allodynia and anxiety-like behaviors. A and B Effects of the Y1 receptor agonist or Y2 receptor agonist on the left hind paw (A) and head withdrawal thresholds (B) in the von Frey test at 1.5 h after VEH or GTN injection. C-F Effects of the Y1 receptor agonist or Y2 receptor agonist on time spent in the open arms (C), the number of open arm entries (D), time spent in the closed arms (E), and the number of closed-arm entries (F) during the EPM test at 4 h after VEH or GTN injection. GTN + saline, n = 10 mice; GTN + Y1 receptor agonist, n = 11 mice; GTN + Y2 receptor agonist, n = 11 mice. Significance was assessed by Kruskal–Wallis H test with Mann–Whitney U post hoc comparison between groups (A and B; *P < 0.05, ***P < 0.001) or by one-way ANOVA with post hoc comparison between groups (C-F; *P < 0.05, **P < 0.01). All data are presented as the mean ± S.E.M