Hypotensive Activity of Tacca chantrieri. and Its Hypotensive Principles

AbstractThe rhizomes of Tacca chantrieri. Andre (Taccaceae) have been used in Chinese medicines for the treatment of various diseases including high blood pressure, burns, gastric ulcers, enteritis, and hepatitis. The rhizomes of this plant have been found to contain a wide array of saponins and other compounds. The aims of the current study were to investigate the hypotensive activity of the ethanol extract (TCE) and both the crude (TCS) and purified saponin extract of T. chantrieri., and thus to characterize the hypotensive principles. TCE and TCS at the dose of 5 mg/kg caused hypotension and bradycardia in normotensive rats under pentobarbital anesthesia. Both TCE and TCS caused a decrease in the force and rate of contractions in isolated rat atria. The vasorelaxant activity of TCE and TCS could be demonstrated when tested on the aortic ring with endothelium intact. It is therefore implied that TCE and TCS exert both their hypotensive effect and bradycardia by affecting the heart as well as blood vesse...