Objective: To evaluate the potential dopaminergic and serotonergic receptor-mediated modulatory effect of the aqueous extract of Sapindus trifoliatus [(ST), (family: Sapindaceae)], a traditional phytomedicine used in the treatment of hemicrania (migraine), using animal models and receptor assays. Materials and Methods: ST (at 20 and 100 mg/kg, i.p. doses) was evaluated for its effect on apomorphine-induced climbing behavior, 5-hydroxytryptophan (l-5-HTP)-induced serotonin syndrome, and

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... duced hyperactivity in mice. The radioligand binding studies for various receptors and enzymes were carried out (outsourced) using standard procedures at 250 μg/ml concentration of ST. Results: ST significantly inhibited the apomorphine-induced climbing behavior, the l-5-HTPinduced serotonin syndrome and MK-801-induced hyperactivity in mice. In the receptor radioligand binding studies, ST exhibited affinity towards dopamine D 2 , 5-HT 2A receptors. Conclusion: The results of the behavioral studies in mice indicate that ST modulated D 2 and 5-HT 2A receptor-mediated paradigms. The radioligand binding studies supported these observations, suggesting the possible involvement of dopaminergic and serotonergic mechanisms in the antimigraine activity of ST.