Effects of GRPr antagonist RC-3095 and NMBr antagonist PD168368 on intrathecal GRP- and NMB-induced scratching, respectively.

Antagonists were administered intrathecally 10 min prior to GRP or NMB. Mice were observed immediately after the administration of GRP or NMB up to 1 h. Top panel shows changes in the dose response curve of GRP-induced scratching following RC-3095 pretreatment (A). Bottom panel shows changes in the dose response curve of NMB-induced scratching following PD168368 pretreatment (B). Each value represents mean ± SEM (n = 6) for number of scratching bouts observed across 1 h. Different symbols represent different dosing conditions.