Figure 4

CGRP-IR downregulation is prevented by JNK blockade in L4 primary sensory neurons of wt mice. (A) Effect of D-JNKI-1 on SNT‒induced CGRP expression in L4 DRG neurons. CGRP-IR in neurons was quantitated with the Neurolucida software, and expressed as a percentage of positive neurons. *p < 0.05 and ***p < 0.001 by tTest compared with unoperated wt; n = 11. #p < 0.05 by tTest compared with SNL ipsi; n = 8. Values are mean + SEM (B-E). Representative 20X DRG sections immunoistochemically stained for CGRP: (B) baseline expression of CGRP-IR in the DRGs of the wt mice; (C) a significant decrease in CGRP-IR occurs in injured DRGs after 72h; (D) D-JNKI-1 alone has no effect on baseline CGRP-IR levels; (E) D-JNKI-1 treatment prevents downregulation of CGRP-IR. Scale bar = 50 μm.