Fig. 4.

Long-term reduction of U50488-mediated inhibition of PGE₂-stimulated thermal allodynia by norBNI is peripherally mediated. Rats received injections (i.pl.) of norBNI (30 ng) or vehicle (Veh). Two (A) and 7 (B) days later, Rats received coinjections (i.pl.) of PGE₂ (0.3 µg) with U50488 (0.1 µg) in either the contralateral or the ipsilateral hind paw. PWL in response to application of a radiant heat stimulus to the ventral surface of the hind paw was measured in duplicate before and at 5-minute intervals following the coinjection of PGE₂ plus U50488. Data are expressed as the mean ± S.E.M. of the AUC for each group of six animals. Data were analyzed with one-way ANOVA and Dunnett’s post hoc test. ***P < 0.001 compared with vehicle (Veh)-treated ipsilateral paw. Time course data are provided in Supplemental Fig. 4.