Fig. 6
5-HT3 receptors were involved in stress-induced wide-spreading hyperalgesia in female rats with orofacial pain. a The expression of 5-HT3A receptors in L4-L5 spinal dorsal horn in the E2 + CFA + FS group (n = 5) significantly increased when compared with that in the oil + saline + non-FS group (n = 5). § p < 0.05 vs the oil + saline + non-FS group. b 5-HT3 receptor antagonist Y-25130 but not vehicle blocked thermal hyperalgesia induced by stress combined with orofacial inflammation in female rats. *** p < 0.001 vs baseline. The thermal withdrawal latency significantly decreased on day 2 and day 6 post FS stress in saline treated rats (E2 + CFA + FS + saline group, n = 12) compared with Y-25130 treated (E2 + CFA + FS + Y-25130 group, n = 7). ## p < 0.01 vs the E2 + CFA + FS + Y-25130 group at the same time point. c Y-25130 blocked mechanical allodynia induced by stress in female rats with orofacial inflammation. *** p < 0.001 vs baseline. The mechanical withdrawal threshold significantly decreased for 15 days post FS stress in saline treated rats (E2 + CFA + FS + saline group, n = 12) compared with Y-25130 treated (E2 + CFA + FS + Y-25130 group, n = 7). ##, ### p < 0.01, 0.001 vs the E2 + CFA + FS + Y-25130 group at the same time point