Fig. 2

Infraorbital nerve constriction induced hyperalgesia and upregulated GFAP expression in the TNC (A) Schematic diagram of infraorbital nerve constriction in rats. B Immunofluorescence staining showed that GFAP fluorescence intensity was significantly increased in the TNC of the TN group compared to that of the sham and naïve groups. Scale bar = 50 μm. C Quantification of GFAP immunostaining in the TNC of different groups. Data are presented as the mean ± SD, n = 5/group, two tailed Welch’s t-test, ****p < 0.0001 compared with the sham group. D Pictorial diagram of the behavior test for pain assessment (E) Representative trajectory of TN, sham and naïve groups in the OFT. F Number of explored areas and (G) mobility rate (in percentage) in each group before (baseline) and after (week 1 and week 3) surgery. H–L The mechanical pain threshold in the von Frey filament test in ipsilateral and contralateral whisker pads. J The thermal pain threshold. K-L The pressure threshold in air puff test in ipsilateral and contralateral whisker pads. ****, p < 0.0001, ordinary two-way ANOVA followed by Sidak’s multiple comparisons among groups. Data are displayed as the means ± SD, n = 20(TN), 20( sham), 5 (naïve)