Figure 1.

Acute administration of myrcene dose-dependently reduced secondary allodynia in adjuvant monoarthritic knees. Local injection of myrcene around the arthritic knee reduced von Frey hair withdrawal threshold at day 7 of the model with the maximal response occurring 120 min after drug administration (A). ** p < 0.01, * p < 0.05 (5 mg/kg dose) ⁺ p < 0.05 (1 mg/kg dose) two-factor RMANOVA with Bonferroni’s post hoc test. Pre-treatment of arthritic animals with either the CB₁-receptor antagonist AM281 (75 µg s.c.) or the CB₂-receptor antagonist AM630 (75 µg s.c.) blocked the analgesic effect of myrcene (B). Antagonists alone were not significantly different from vehicle. ns—not significant, **** p < 0.0001, *** p < 0.001, one-factor RMANOVA with Bonferroni’s post hoc test. Data are means ± S.E.M.