Effects of a single injection of vehicle, AA-5-HT (0.1-0.25-1 nmol) (A), AM251 (0.25-0.5 nmol) (B), AM251+AA-5-HT (C), I-RTX (0.25-0.5-1 nmol) (D) or URB 597 (1-2-4 nmol) (E) on mechanical withdrawal threshold (mean ± S.E.M.) in spared nerve injury (SNI) rats. Each point represents the mean ± S.E.M. of 8-10 rats per group. *p < 0.05 vs SNI/veh.