Figure 1

CFA induced inflammation caused mechanical allodynia but not axon sprouting of labeled trigeminal Aβ afferents. (A) Unilateral injection of CFA into whisker pad induced mechanical allodynia on the ipsilateral side. Higher behavior score indicated an increased aversive response to von Frey filament stimulation. Results represent means ± SEM. P-values represent comparison to sham values (*P < 0.05). Differences were determined by Student’s t test between two groups, or one-way ANOVA followed by post-hoc Bonferroni test for multiple groups. n = 6 mice for each group. (B) Schematic of experimental procedure for results shown in C-E. (C) Representative spinal caudalis (SpC) section from Pv-CreER; Ai14 transgenic mice. Red: labeled Aβ axon collaterals; Green: IB4-488 staining marked lamina II; Blue: DAPI. Left side is CFA injected side (3 days post injection), while right side is control IFA injected side. (D-E) High magnification images of boxed regions in C. (F) Schematic of experimental procedure for results shown in G-I. (G) Representative spinal caudalis (SpC) section from Pv-CreER; Ai14 transgenic mice. Red: labeled Aβ axon collaterals; Green: IB4-488 staining marked lamina II; Blue: DAPI. Left side is CFA injected side (10 days post injection), while right side is control IFA injected side. (H-I) High magnification of boxed regions in G. Scale bar: 100 μm.