Interaction between Mu and Delta Opioid Receptor Agonists in an Assay of Capsaicin-Induced Thermal Allodynia in Rhesus Monkeys
Figure 1
Antiallodynic effects produced by methadone administered alone or in combination with SNC80 or SNC67 (a), methadone after pretreatment with 0.1 mg/kg naltrexone or 1.0 mg/kg naltrindole (b), and 0.9 : 1 SNC80/methadone after pretreatment with naltrexone or naltrindole (c). Abscissae: dose methadone in mg/kg (log scale). Ordinates: percent maximum possible effect (%MPE). All points show for three monkeys. ED50 values are compared in Table 1. Data for methadone alone and 0.9 : 1 SNC80/methadone at doses of 0.32 and 1.0 mg/kg methadone in the left panel were compared by 2-way ANOVA (see text for details). The asterisk in the left panel indicates a significant difference from methadone alone.
