GAP43-IR downregulation is partially prevented by JNK blockade in L4 primary sensory neurons of wt mice. (A) The effect of D-JNKI-1 on SNL‒induced GAP43 expression in L4 DRG neurons. The immunoreactivity for GAP43 in DRG neurons was quantitated with the Neurolucida software, and expressed as a percentage of positive neurons. **p < 0.01 by tTest compared with unoperated wt; n = 8. #p < 0.05 by tTest compared with SNL ipsi; n = 8. Values are mean + SEM. (B-E)Representative DRG sections immune-stained for GAP43: (B) unoperated wt displays faint immunohistochemical labelling; (C) a significant increase in GAP43-IR occurred in DRGs, 72h after nerve injury; (D) D-JNKI-1 alone has no effect on baseline GAP43 levels; (E) D-JNKI-1 treatment partially prevents GAP43-IR upregulation on the lesioned side. Scale bar = 50 μm.