Fig. 2. Effect of excitatory amino acid receptor antagonists on the development of withdrawal to punctate mechanical stimulation. Rats were tested before incision, from 1 to 6 h after incision and on postoperative days 1–6. The results are expressed as median (horizontal line) with first and third quartiles (boxes) and 10th and 90th percentiles (vertical lines). (A ) Withdrawal thresholds in eight rats receiving vehicle administration before incision. (B –D ) Withdrawal thresholds in eight rats administered NBQX (B ), MK-801 (C ), or (+)-MCPG (D ) before incision. (E and F ) Withdrawal thresholds after incision in eight vehicle-treated rats (E ) and in eight rats administered NBQX after incision (F ). *P < 0.05 versus preincision by Friedman and Dunnett test. †P < 0.05 versus vehicle by Kruskal-Wallis and Dunn test.