Figure 2 - Effect of indomethacin on the intensity of PGE2 hyperalgesia in chronically cannulated (Cn, triangles), sham-operated (Sh, squares) and naive (Nv, circles) animals. Indomethacin was administered via an intrathecal (it) cannula (panel A), directly into the subarachnoid space (panel B) or systemically (ip, panel C) 30 min before intraplantar injection of PGE2 (10 ng/paw). Each point represents the mean reaction time (s) ± SEM of 5-13 animals per group measured 3 h after the hyperalgesic challenge. The data were analyzed by one-way ANOVA followed by Duncan's test (asterisks indicate significant differences for each dose, P<0.05).