Fig. 4.

The antinociception induced by 75, 150, 300 mg/kg (i.p.) protocatechuic acid, 300 mg/kg (i.p.) dipyrone, 5 mg/kg (i.p.) WIN 55,212–2 and the combination of 150 mg/kg (i.p.) protocatechuic acid and 2.5 mg/kg (i.p.) WIN 55,212–2 in the acetic acid-induced writhing test. PCA: Protocatechuic acid. WIN: WIN 55,212–2. ^*P < 0.05, ^**P < 0.01, ^***P < 0.001: significant difference based on the control group. One-way ANOVA followed by Tukey’s HSD multiple comparison post-hoc test was performed. Values expressed as mean ± S.E.M. (n = 8)