Antinociceptive Activity of Methanol Extract of Dioscorea Pentaphylla Linn. Leaves in Mice

Background: Dioscorea pentaphylla L. a common plant of Dioscorea family commonly called five leaves in Bangladesh. The plant contains the alkaloid, carbohydrate, tannin, gum protein, steroid, glycoside, flavonoids. It is used as an analgesic, anti-inflammatory, and Powder of plant extract given orally in abdominal pain after delivery. The aim of the study: The present study was designed to evaluate chemical constituents and to investigate the antinociceptive activity of methanol extracts of Dioscorea pentaphylla (MEDP). Methods: The antinociceptive activity of MEDP was investigated using heat-induced (hot-plate and tail-immersion test) and chemical-induced (acetic acid, Formalin-induced) nociception models in mice at 200 & 400mg/kg doses. Result: Oral administration of the methanolic extract of leaves of Dioscorea pentaphylla L. (200 & 400 kg/mg) dose-dependently reduced nociceptive response to acute pain in acetic acid induced writhing. For acetic acid-induced writhing test highest inhibition (55.40 %) was found in case of highest dose (400 mg/kg) for leaf extract. Whereas standard drug diclofenac sodium causes (46.93%) writhing inhibition. Formalin-induced nociception test showed the significant effect in (200 and 400 mg/kg) for both dosages. On the other hand, MEDP showed the significant effect in hot plate, tail immersion test, at high dose (400mg/kg). Conclusion: MEDP showed significant antinociceptive activity via a multifactorial mechanism of action, indicating that the extract may be useful in the development of a new analgesic drug.