The study of analgesic effects of Leonurus cardiaca L. in mice by formalin, tail flick, and hot plate tests

Objectives: Leonuruscardiaca, commonly known as motherwort, is a member of the Lamiaceae family. It has a number of interesting biological activities, for example, sedative and hypotensive, antioxidant, anti-inflammatory and antimicrobial activities. The aim of the present study was to investigate the effect of alcoholic extract of aerial part of Leonuruscardiaca on nociceptive response using formalin, tail flick and hot plate tests in mice.Materials Methods:The ethanolic extract from the aerial part of Leonuruscardiaca after intraperitoneal administration at doses of 125, 250, and 500 mg/kg was evaluated against pain using formalin, tail flick and hot plate tests.One-way analysis of variance (ANOVA) test was used to ascertain the significance of variations between the times of licking in formalin test. Two-way repeated measure ANOVA test used for assay the differences in reaction time in tail flick and hot plate tests. All data were considered significant at P≤0.05.Results Conclusion: The acute treatment of mice with an ethanolic extract at doses of 500 and 250 mg/kg by intraperitoneally administration produced a significant antinociceptive in the first and second phases of formalin test, respectively(P≤0.05). The hot plate and tail flick tests showed an increase in the antinociceptive effect at dose 500 mg/kg (P≤0.01). These results suggest that Leonuruscardiaca possesses central and peripheral antinociceptive actions.