Antinociceptive Activity of Zanthoxylum piperitum DC. Essential Oil

Figure 2

Effect of essential oil from Zanthoxylum piperitum DC. on formalin-induced licking in mice (first and second phases). Animals were pretreated with ZPEO (10, 30, or 100 μL/kg, p.o.), acetylsalicylic acid (ASA, 200 mg/kg, p.o.), morphine (2.5 mg/kg, p.o.), or vehicle (oil). Results are presented as mean ± SD ( = 6–10). Statistical analyses were performed using GraphPad Prism version 5.1 software, by one-way ANOVA with Dunnett’s posttest with multiple comparisons against vehicle-treated group ().