Antinociceptive and antiinflammatory effects of Teucrium hyrcanicum aqueous extract in male mice and rats

Abstract Introduction: The aim of this study was to investigate the antinociceptive and antiinflammatory effects of Teucrium hyrcanicum aqueous extract in male mice and rats. Methods: To assess the antiinflammatory effect, we used carrageenan- and dextran-induced paw oedema and for determination of the antinociceptive effect, acetic acid-induced writhing, tail flick and formalin pain tests were used. Results: The extract of T. hyrcanicum (50–200 mg/kg) and acetylsalicylic acid (100 mg/kg) produced a significant inhibition of the second phase response in the formalin pain model (P<0.01), while only the high dose of the extract (200 mg/kg) showed an analgesic effect in the first phase. The extract also inhibited acetic acid-induced abdominal writhes in a dose-dependent manner. The tail flick latency was dose dependently enhanced by the extract but this was significantly lower than that produced by morphine 10 mg/kg (P<0.05). The extract (25–250 mg/kg) administered 1 h before carrageenan-induced paw swelling produced a dose dependent inhibition of the oedema. No effect was observed with the dextran-induced oedema model. Conclusion: The obtained data suggest antiinflammatory and analgesic effects for the aqueous extract of Teucrium hyrcanicum, which may be mediated via both peripheral and central mechanisms. The presence of alkaloids, flavonoids and triterpenoids might be responsible for the antiinflammatory activity of this plant.