The antidepressant-like effect of Mentha spicata essential oil in animal models of depression in male mice

Background & Objective: Previous researches have revealed analgesic and sedative properties of Mentha spicata (MS). The aim of present study was to evaluate the antidepressant effects of MS essential oil in forced swim test (FST) and tail suspension test (TST) in male mice. Materials & Methods: In this experimental study, 84 male mice were randomly divided into 14 groups of 6: Negative control groups received normal saline (10 ml/kg,i.p.), positive control groups received fluoxetine (20mg/kg, i.p.) and imipramine (30mg/kg) and treatment groups received MS essential oil (30, 60,120 and 240 mg/kg i.p.). In FST, immobility time, swimming time and climbing time and immobility time in TST were recorded in six minutes. Results: Findings indicated that essential oil at doses of 120 and 240 mg/kg, fluoxetine and imipramine reduced immobility time compared to control group in FST and TST (p<0.001). Also, this essential oil and fluoxetine increased swimming time (p<0.001) without significant change of climbing time (p>0.05). In contrast, imipramine increased climbing time without any significant change in swimming time (p>0.05). Conclusion: Based on the findings of the present study, MS essential oil has antidepressant-like activity similar to fluoxetine and probably their compounds (especially carvone) with serotonergic mechanism induced their effect. However, further studies are needed to determine the precise mechanism of its action.