Fig. 5.

Effects of l–arg (a) or ODQ (b) on PECN-induced antinocicpetive activity assessed using the acetic acid–induced abdominal constriction test in mice. Animals were treated with PECN (500 mg/kg, p.o.) or vehicle (10 mL/kg, p.o.) 60 min before acetic acid (0.6%, 10 mL/kg, i.p.) treatment. l–arg (20 mg/kg, i.p.) or ODQ (2 mg/kg, i.p.) were administered 5 min before PECN (500 mg/kg, p.o.) or vehicle (10 mL/kg, p.o.). Each column represents the mean ± SEM of six mice. Statistical analyses were performed using one–way ANOVA followed by Dunnett’s post hoc test. *p < 0.05, ***p < 0.001 compared to control group; ^#p < 0.05, ^##p < 0.01, and ^###p < 0.001 compared to 500 mg/kg PECN–treated group