Anxiolytic and antiamnesic potentials of <i>Terminalia</i> A. Chev (Combretaceae) stem and root bark methanol extracts in mice.

Background: Terminalia ivorensis (Chev) stem bark is used in combating mental illnesses in African traditional medicine. Previous studies demonstrated its antipsychotic properties but there are no documented reports on the anxiolytic and antiamnesic properties of Terminalia ivorensis. Hence, this study investigated the anxiolytic and antiamnesic potentials of methanol stem bark and root barkextracts of T. ivorensis in mice. Methods: The anxiolytic potentials of stem and root bark methanol extracts at 100, 200 and 400 mg/kg b.w were investigated using mouse model of anxiety (elevated plus maze test), while the antiamnesic potentials were assessed using mouse model of short term memory assessment (Y-maze test). Results: The stem and root bark methanol extracts at all the tested doses, significantly (p≤0.05) elongated the percentage number of entries into the open arm of the elevated plus maze, while the duration of stay on the open arm of the elevated plus maze was only significant (p≤0.05) at 100 mg/kg for stem bark extract. Stem and root bark extracts, at all the tested doses, significantly (p≤0.05) reduced the anxiety indices of mice indicative of antianxiety potentials. Both extracts showed significant (p≤0.05) dose-dependent decrease in percentage correct alternations compared to the scopolamine control group indicating antiamnesic effect. Conclusion: This study revealed that stem and root bark extracts may possess anxiolytic and antiamnesic effects in mice which justify its use in treating mental illnesses in traditional medicine.