Intestinal Relaxant Activity of Crude Extract of Aesculus Indica and Its Underlying Mechanism
Abstract
Objective: To investigate the effects of Aesculus indica on rabbit’s jejunum and its underlying mechanism. Study Design: Experimental study. Settings: Pharmacy Department, Bahauddin Zakria University, Multan, Pakistan. Duration: May 2017 to October 2017. Methods: The action of crude extract on rabbit’s jejunum was examined. Each jejunal tissue of 1-1.5 cm in length was mounted in 15ml Tyrode’s solution. The spasmolytic activity of crude extract of Aesculus indica was determined by treating each jejunal tissue with plant extract in doses of 0.01, 0.03, 0.1, 0.3, 1, 3, 5, 10 µM cumulatively. Response was determined by percentage change in jejunal tissue contraction. To demonstrate the calcium channel blocking action of test plant, each jejunal preparation was first stabilized in Tyrode’s solution having normal composition. To remove calcium from tissues, they were placed in calcium- free Tyrode’s solution containing EDTA for thirty minutes. This solution was then replaced with potassium rich and calcium free solution. Verapamil (3µM) was used as a positive control. After incubation period of thirty minutes, control concentration-response curves of Ca++ (CaCl2) were achieved. Results: Aesculus indica produced spasmolytic effect on rabbit’s jejunum in normal Tyrode’s solution. Further evaluation of effect of Aesculus indica did not show the absolute inhibition of low K+ induced contraction. To confirm whether the spasmolytic effect of Aesculus indica is through inhibition of Ca+2 channels or the opening of the K+ channels, its effect was seen on the low K+ (25mM) and high K+ (80mM) induced contraction. Aesculus indica at the high dose did not show the absolute inhibition of low K+ induced contraction. The crude extract of Aesculus indica showed concentration dependent relaxation of spontaneous, high K+ (80mM) induced contraction with relevant EC50 values of 0.1083mg/ml (0.04793-0.2447, 95 %CI). Conclusion: The present study shows that Aesculus indica has spasmolytic effect which is due to Ca+ channel blocking activity.