Figure 3.

ERK1 is not necessary for CFA-induced hypersensitivity. A, To measure CFA-induced heat hypersensitivity, WT (n = 10) and ERK1 KO (n = 10) littermates were injected with CFA subcutaneously into the plantar surface of the hindpaw. Paw withdrawal latencies to a radiant heat stimulus were then obtained from both hindpaws, ipsilateral and contralateral to CFA injection, using a Hargreaves-style apparatus. Data were normalized to preinjection baseline paw withdrawal latencies within subject and plotted as percentage baseline. B, To measure CFA-induced mechanical allodynia, WT (n = 6) and ERK1 KO (n = 6) littermates were injected with CFA, and paw withdrawal thresholds to light touch were measured using von Frey filaments. In all cases, there was no statistically significant difference between genotypes. Error bars indicate SEM.