Paradoxical effects of ginkgolide B on cardiomyocyte contractile function in normal and high-glucose environments

作     者：JihyeKIM CindyXFANG 

作者机构：Center for Cardiovascular Research and Alternative Medicine Division of Pharmaceutical Sciences Laramie USA University of Wyoming WY 82071 

出 版 物：《Acta Pharmacologica Sinica》 (中国药理学报(英文版))

年 卷 期：2006年第27卷第5期

页      面：536-542页

核心收录：

学科分类：1008[医学-中药学(可授医学、理学学位)] 1006[医学-中西医结合] 100602[医学-中西医结合临床] 10[医学] 

基　　金：This work was supported in part by the American Heart Association.JK was supported in part by the University of Wyoming Experimental Program to Stimulate Competitive Research 

主　　题：ginkgolide B cardiomyocytes contraction Ca2+ regulatory protein 

摘      要：Aim:Ginkgo biloba extract is a natural product used widely for cerebral andcardiovascular *** is mainly composed of terpene lactones (ginkgolide Aand B) and flavone glycosides (eg quercetin and kaempferol).To better under-stand the cardiac electromechanical action of Ginkgo biloba extract in normal anddiabetic states,this study was designed to examine the effect of ginkgolide B oncardiomyocyte contractile function under normal and high-glucose ***:Isolated adult rat ventricular myocytes were cultured for 6h in a serum-free medium containing either normal (NG;5.5mmol/L) or high (HG;25.5mmol/L)glucose with or without ginkgolide B (0.5-2.0μg/mL).Mechanical propertieswere evaluated using the IonOptix MyoCam *** properties ana-lyzed included peak shortening (PS),maximal velocity of shortening/relengthening(±dl/dt),time-to-PS (TPS) and time-to-90% relengthening (TR90).Levels of essen-tial Ca2+regulatory proteins sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA2a),phospholamban (PLB) and Na~+-Ca2+exchanger (NCX) were assessed by ***:Ginkgolide B nullified HG-induced prolongation in ***,ginkgolide B depressed PS,±dl/dt and shortened TPS in NG and *** B also prolonged TR90in NG *** blot analysis re-vealed that HG upregulated SERCA2a and downregulated PLB expression with-out affecting that of *** B disrupted the NG-HG response pattern inSERCA2a and NCX without affecting that of ***:Ginkgolide Baffects cardiomyocyte contractile function under NG or HG environments in aparadoxical manner,which may be attributed to uneven action on Ca2+regulatoryproteins under NG and HG conditions.