Figure 4

Injection of CFA in the TMJ activates resident TG macrophages. (A-B') ED1 immunostaining (green) of activated macrophages in the V3-mandibular TG division, showing upregulation at both 24 h (A, A') and 72 h (B, B') post CFA injection. Nuclei were labeled with the Hoechst 33258 dye (blue). Scale bars: 20 μm. (C-E) Densitometric analysis of ED1 immunoreactivity, showing that, at 24 h post CFA injection, a significant upregulation of ED1 staining was detected in any of the three TG divisions, and that a lower, although not statistically significant, effect was also present at 72 h. (F-H) Results from densitometric analysis were fully confirmed by counting the number of ED1⁺ cells in an identical area for each coverslip. Since no significant differences between saline-injected rats at 24 h and 72 h have been observed, data have been pooled together, and shown here as "saline". Data are expressed as number of ED1⁺ macrophages per counting field at 40× magnification, and refer to 3 independent experiments. * p < 0.05, ** p < 0.01, and *** p < 0.001 compared to the contralateral side; one-way ANOVA.