Myeloperoxidase (MPO) activity and expression of mRNA for TNF-α, IL-1β and IL-6 in formalin-induced inflammatory muscle pain. (A) Myeloperoxidase activity and mRNA quantification for (B) TNF-α, (C) IL-1β and (D) IL-6 in the muscle of formalin-injected mice. Mice were pretreated, i.p., with saline, DALBK or HOE 140. Data were normalized to mRNA levels for GAPDH. Control mice received an i.m. injection of 0.9% saline solution (50 µL per site). Data represent the mean ± SEM (n= 3–5). The symbols denote a significant difference: *P < 0.05 compared to the control (saline i.m.) group and #P < 0.05 compared to the formalin i.m. group. Statistical analyses were performed by one-way anova followed by Bonferroni's test.