Figure 1.

Effects of subcutaneous 1 mL/kg saline, 0.05 mg/kg subcutaneous buprenorphine, 10 mg/kg intraperitoneal tramadol, and 10 mg/kg intraperitoneal tramadol plus 80 mg/kg subcutaneous gabapentin on latency of paw withdrawal to radiant heat stimuli (s, mean ± SEM) induced by plantar incision on (A) ipsilateral and (B) contralateral hindpaws. Each group contained 6 rats. *, Significant (P < 0.05) difference compared with baseline value for group; #, significant (P < 0.05) difference compared with value for the saline group at the same time point.