Evaluation of analgesic and anti-inflammatory properties of the Allium cepa extract in rats

Abstract

Background: The onion plant (Allium cepa) is the most widely cultivated species of the genus Allium. It has antibiotic, antidiabetic, antihypercholesterolemic, antioxidant, hemostatic, antimutagenic effects. The current study is aimed to evaluate analgesic and anti-inflammatory properties of Allium cepa extracts in rat models.Methods: In this study analgesic activity in rats is tested by Eddy’s hot plate method, tail flick method. In Eddy’s hot plate method rats are individually placed on the heated plate of the analgesic meter maintained at 550C and mean reaction time was calculated at regular time intervals. In tail flick method the tail withdrawal from the heat (flicking response) is taken as the end point. Anti-inflammatory property is studied by carrageenan induced paw edema model, in which the paw volume is measured with a plethysmograph.Results: In Eddy’s hot plate method the mean reaction time increased significantly (p<0.05) with high dose of Allium cepa at 1 hour and 2 hours when compared to control. In tail flick method the mean reaction time is increased significantly (p<0.05) with high dose of Allium cepa at 1 hour and 1.5 hour when compared to control. In carrageenan induced paw edema method Allium cepa exhibited anti-inflammatory activity by significant (p<0.05) suppression of paw edema when compare to control at 1 hour after carrageenan injection to rat paw.Conclusions: Allium cepa has significant analgesic and anti-inflammatory activity in hot plate, tail flick and carrageenan induced paw edema model.