Anti-dopaminergic Activity of Vitex negundo Linn Leaves

Objective: The objective of this study was to investigate the effect of acetone soluble fraction of methanolic extract of leaves of Vitex negundo on dopaminergic function. Methods: The effect of acetone soluble fraction of methanolic extract of leaves of Vitex negundo (50 and 100 mg/kg, i.p.) was studied on haloperidol-induced catalepsy in mice, amphetamine-induced stereotyped behavior in rats and dopamineinduced contraction of isolated vas deferens preparation of rat. Results: The acetone soluble fraction of methanolic extract of V. negundo significantly potentiated haloperidol-induced catalepsy, antagonized dose dependent amphetamine- induced stereotyped behavior, and also antagonized dopamine-induced contractions of rat vas deferens. Conclusion: The results suggest that the methanolic extract of Vitex negundo possessed antidopaminergic principles.