Investigations of<i>Sapindus trifoliatus</i>in dopaminergic and serotonergic systems: Putative antimigraine mechanisms

Abstract

OBJECTIVE: To evaluate the potential dopaminergic and serotonergic receptor-mediated modulatory effect of the aqueous extract of <i>Sapindus trifoliatus</i> [(ST), (family: Sapindaceae)], a traditional phytomedicine used in the treatment of hemicrania (migraine), using animal models and receptor assays.<br>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 (<i>l</i>-5-HTP)-induced serotonin syndrome, and MK-801-induced 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. <br>RESULTS: ST significantly inhibited the apomorphine-induced climbing behavior, the <i>l</i>-5-HTP-induced serotonin syndrome and MK-801-induced hyperactivity in mice. In the receptor radioligand binding studies, ST exhibited affinity towards dopamine D2, 5-HT2A receptors. <br>CONCLUSION: The results of the behavioral studies in mice indicate that ST modulated D2 and 5-HT2A 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.