Anti-nociceptive effect in mice of thillai flavonoid rutin.

We investigated the anti-nociceptive effect of Excoecaria agallocha (E.agallocha) against chemically and thermally induced nociception, Albino mice received a dose of 10, 15, 20, or 25 mg/kg of alkaline chloroform fraction (Alk-CF) of E.agallocha by oral administration. Compared with controls, Alk-CF decreased the writhing numbers (P<0.01) in a dose dependent manner. Further we determined that, Alk-CF contained, a potent compared to control, also potent anti-nociceptive agent that acted via opioid receptors and using HPLC, identified this compound as Rutin. Docking simulation demonstrated that Rutin interacted strongly with cyclooxygenase, forming a number of specific hydrogen bonds. In conclusion we have identified peripheral and central anti-nociceptive activities of E.agallocha that involve opioid receptor, and in which the active compound is Rutin.