Figure 5.

Effects of spinal adrenergic (A) and (B) and 5-HT (C) and (D) receptor antagonism on combination treatment analgesia in cold and mechanical allodynia. Mice were divided into six groups that received each antagonist or appropriate vehicle intrathecally (i.t.); normal saline (NS), 20% dimethyl sulfoxide (DMSO), prazosin, idazoxan, methysergide or MDL-72222 at 20 min before combination treatment (BVA, s.c., 1 mg/kg and VLX, i.p., 40 mg/kg). Acetone test and von Frey test were performed twice; just prior to the intrathecal injection (Before) and 60 min after combination therapy (After). Data are expressed as mean ± S.E.M.; * p < 0.05, ** p < 0.01, *** p < 0.001, vs. Before; by Bonferroni post-hoc test after two-way ANOVA.