Figure 1.

Effect of systemic administration of pentoxifylline on the writhing response induced by zymosan, acetic acid or iloprost in mice. The number of writhes was determined for the interval of 0–30 min, after i.p. injection of zymosan (1 mg mouse⁻¹, panel a), acetic acid (0.1 ml 10 g body weight⁻¹of a 0.6% solution, v v⁻¹) (panel b) or iloprost (0.5 μg mouse⁻¹; panel c). Pentoxifylline (PTF; 0.1–1.6 mg kg⁻¹; i.p.) or vehicle (saline; S) was given 30 min before stimulus administration. In panel c, the mice were pretreated with vehicle or pentoxifylline (PTF; 1.6 mg kg⁻¹) 30 min before iloprost. Results are expressed as means±s.e.m. for groups of six mice. Asterisks indicate statistically significant differences between groups and respective controls (^*P<0.05; ^**P<0.001).