Table of Contents Author Guidelines Submit a Manuscript
Evidence-Based Complementary and Alternative Medicine
Volume 2013, Article ID 481830, 11 pages
http://dx.doi.org/10.1155/2013/481830
Research Article

Inhibitory Effects of Glycyrrhetinic Acid on the Delayed Rectifier Potassium Current in Guinea Pig Ventricular Myocytes and HERG Channel

1Beijing Hospital of Integrated Traditional Chinese and Western Medicine, Beijing 100039, China
2Beijing Institute of Radiation Medicine, Beijing 100850, China

Received 19 March 2013; Revised 7 July 2013; Accepted 11 July 2013

Academic Editor: Hao Xu

Copyright © 2013 Delin Wu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Background. Licorice has long been used to treat many ailments including cardiovascular disorders in China. Recent studies have shown that the cardiac actions of licorice can be attributed to its active component, glycyrrhetinic acid (GA). However, the mechanism of action remains poorly understood. Aim. The effects of GA on the delayed rectifier potassium current ( ), the rapidly activating ( ) and slowly activating ( ) components of , and the HERG K+ channel expressed in HEK-293 cells were investigated. Materials and Methods. Single ventricular myocytes were isolated from guinea pig myocardium using enzymolysis. The wild type HERG gene was stably expressed in HEK293 cells. Whole-cell patch clamping was used to record ( , ) and the HERG K+ current. Results. GA (1, 5, and 10 μM) inhibited ( , ) and the HERG K+ current in a concentration-dependent manner. Conclusion. GA significantly inhibited the potassium currents in a dose- and voltage-dependent manner, suggesting that it exerts its antiarrhythmic action through the prolongation of APD and ERP owing to the inhibition of ( , ) and HERG K+ channel.