Figure 2

The effect of i.c.v. administration of A-317491 on the inflammatory nociceptive behaviors. (A) For the measurement of formalin-induced nociceptive behavior, the scoring of nociceptive behavior started immediately after the i.pl. injection of formalin into the right hindpaw. The nociceptive behaviors were observed for 60 min and were quantified using a rating scale method by assigning weights for each 5 min. (B) For the measurement of acetic acid-induced nociceptive writhing behavior, counting the number of typical writhing behaviors started immediately after the i.p. injection of acetic acid. The writhing behavior was observed for 60 min and the number of occurrences every 5 min was evaluated. The i.c.v. administration of A-317491 (1 and 10 nmol) or PBS was performed 5 min before the i.pl. injection of formalin or i.p. injection of acetic acid. The values are presented as the means ± S.E.M. *P < 0.05, ***P < 0.05 vs PBS group (n = 5–6).