Fig. 5. Effect of neurotoxic rostral medial medulla (RMM) lesion on thermal hyperalgesia after incision. Primary thermal hyperalgesia after plantar incision was apparent in sham and RMM lesion rats throughout the test period up to day 5. Secondary thermal hyperalgesia after a gastrocnemius incision was not observed in either sham or RMM lesion rats. Data are mean ± SD. Pre = before incision. *Significant decrease in thermal paw withdrawal latency versus before incision (P < 0.05).