(a) Pretreatment with anisomycin (50 mg/kg, s.c. 1 h prior) or with puromycin (15 mg/kg, s.c. for 14 days) significantly blocked the Bv8 (0.5 ng/rat, i.th.)-induced second phase of hyperalgesia. (b) CGRP and SP immunoreactivity in the rat spinal cord at approximately L5 and in the rat DRG L5. During the second phase of Bv8-induced hyperalgesia, the labeling was upregulated in lumbar dorsal horn of spinal cord of rats pretreated with Bv8 (0.5 ng/rat, i.th., 240 min prior to perfusion). No apparent difference in both CGRP and SP immunoreactivity was seen between the tissues from control rat, from tissues taken during the first phase of hyperalgesia, and from rat pretreated with anisomycin and treated with Bv8.