Figure 2.

Enhanced pain behavior in Lmx1b^f/f/p mice after capsaicin injection. A, Left, A significant increase in duration of licking and flinching responses within 5 min after an intraplantar injection of capsaicin in Lmx1b^f/f/p mice (n = 15) compared with wild-type control (n = 14; *p < 0.05, 2-tailed t test). Right, Capsaicin-evoked paw edema measured by the changes of paw diameter 1 h after capsaicin injection (the value 1 h after injection minus the value of the same hindpaw before injection) in Lmx1b^f/f/p mice (n = 9) did not differ from wild-type mice (n = 10). B, Increased mechanical sensitivity measured with von Frey filaments in the ipsilateral hindpaw induced by capsaicin in Lmx1b^f/f/p mice compared with wild-type mice. ^#p < 0.05, two-tailed t test; *p < 0.05, repeated two-way ANOVA. Paw-withdrawal mechanical threshold (in grams) of wild-type mice and Lmx1b^f/f/p mice before or from 30 to 180 min after capsaicin injection was measured, respectively (n = 9–12). ipsi, Ipsilateral; PWT, paw-withdrawal threshold; WT, wild type.