Figure 4.
Effect of the DOR antagonist naltrindole in rats with CFA-induced latent sensitization. A, PWTs of rats (n = 11) injected in the hindpaw with 50 μl of CFA subcutaneously. B, On day 30, these rats received 2.2 nmol naltrindole (a DOR antagonist) intrathecally. C, On day 48, some of the rats (n = 8) received 1 mg/kg naltrindole subcutaneously. Holm-Sidak's post hoc tests of two-way ANOVA: *p < 0.05, ***p < 0.001 compared with baseline (0 d or 0 min). D, PWTs of rats (n = 8) without intrathecal catheters that were injected in the hindpaw with 50 μl of saline subcutaneously. E, On day 30, the saline-injected rats (n = 8) received naltrindole subcutaneously (1 mg/kg).