FIGURE 3.

Reversion of the antiallodynic and antihyperalgesic effects of UFP-512. Reversal of the effects induced by 30 mg/kg UFP-512 on the mechanical allodynia (A) and thermal hyperalgesia (B) induced by CFA, and on the mechanical allodynia (C), thermal hyperalgesia (D), and thermal allodynia (E) caused by CCI, in ipsilateral paws, with the administration of the specific DOR antagonist, naltrindole (4 mg/kg), and the unspecific opioid antagonist, naloxone (1 mg/kg) are shown. The effects of vehicle, naltrindole (4 mg/kg), or naloxone (1 mg/kg) administered alone are also represented. UFP-512 was intraperitoneally injected 1 h before testing while both naltrindole and naloxone were subcutaneously injected 30 min before testing. For each test, ^∗ represents significant differences compared to the other groups (P < 0.05; one-way ANOVA, followed by the Student–Newman–Keuls test). Data are expressed as mean values of maximal possible effect (%) for mechanical allodynia and thermal hyperalgesia, and inhibition (%) for thermal allodynia ± SEM (six animals for each group).