Effects of BM-21 on the thermal nociception and acetic acid writhing test. A) In the hot plate test the use of BM-21 (40 - 1000 mg kg-1) and 15 mg kg-1 indomethacin increased the latency of response measured 90 min after drug administration. Control = 3.3 s (dotted line). * P ≤ 0.05, ** P ≤ 0.001. In this and following graphs each bar represents mean ± SE, marks * and ** indicate significantly different from control (P ≤ 0.05, P ≤ 0.001) (one-way ANOVA and Student's t-tests). B) Number of contortions and stretches generated by the intraperitoneal injection of acetic acid measured in control and after 90 min of BM-21 or indomethacin administration.