Figure 2.

Formalin-induced spontaneous nociceptive responses are preserved in ERK1 KO mice. The amount of time spent in spontaneous nociceptive behaviors after 2% formalin injection (licking and lifting of the injected paw) was recorded from WT (n = 16) and ERK1 KO (n = 14) littermates and plotted in 5 min bins. No statistically significant difference between WT and ERK1 KO was detected over the course of the 60 min trial or in total time spent in the first phase (0–5 min, bottom left graph) or second phase (5–40 min, bottom right graph) of nociceptive behaviors. Error bars represent SEM.