Evaluation of the anxiolytic effects of the aqueous and ethanolic extracts of the leaves and bark of Annona muricata using the elevated plus maze test

Abstract

Introduction: Natural products since time immemorial have been the source of traditional medicine. A number of well-known anxiolytic agents currently used have several side effects that limit their use. Among medicinal plants, leaves of Annona muricata (AM) are being recommended by traditional healers for the management of anxiety. This study is performed to evaluate the anxiolytic activity of the aqueous and ethanolic extracts of the leaves and bark of Annona muricata. Methodology: Aqueous and ethanolic extracts of the leaves and bark of Annona muricata were prepared and assessed for anxiolytic effect using the elevated plus maze (EPM) model. The antianxiety activity of the extracts were compared to the control (distilled water 10ml/kg) and standard drug Diazepam (5mg/kg). Results and discussion: All doses of the aqueous leaf extract of Annona muricata exhibited significant increase in mean entries into open arms (P<0.01) and mean time spent in open arms (P<0.05) compared to the control. 100mg/kg and 400mg/kg of the ethanolic bark extract of Annona muricata showed significant increase in open arm entries (P<0.01) with 100mg/kg also showing an increase in time spent in open arms which was significant. Conclusion: This study demonstrated that both the aqueous and ethanolic extracts of the leaves and bark of Annona muricata exert an anxiolytic effect on rats which substantiates its traditional use in the management of anxiety.