Effects of Electric Stimulations Applied During Absolute Refractory Period on Ventricular Muscle from Rabbits
张海柱
崔长琮
赵晓静
周忠
1.Department of Cardiology,First Hospital of Xi'an Jiaotong University,Xi,an 7l0061,P R Cina2.Department of Cardiology,First Hospital of Xi'an Jiaotong University,Xi,an 7l0061,P R Cina3.Department of Cardiology,First Hospital of Xi'an Jiaotong University,Xi,an 7l0061,P R Cina4.Department of Cardiology,First Hospital of Xi'an Jiaotong University,Xi,an 7l0061,P R Cina
摘要：Objectives To investigatethe influences of electric signals applied during absoluterefractory period(ARP)on the contractility of isolatedpapilary muscle from rabbits.Methods Papillarymuscle was exercised from the right yentricle and waspaced at 1 Hz.Biphasic square wave current pulse wasdelivered during the absolute refractory period(calledCCM)in isolated,superfused,isometrically contractil-ity rabbit papillary muscle.The peak tension(PT)ofpapillary muscle,as well as maximum positive tensionchange(+dT/dtmax),were observed.ResultsCompared with the baseline,both PT and+dT/dtmaxsignificantly increased during CCM stimulation by18.2%and 21.4%respectively(P＜0.05).In ad-dition,PT increased significantly with one or two beatsfollowing CCM signal application and reached a newsteady state level after a few beats.Once the CCM signals were turned off,the PT returned to the approximatelv baseline level(P＜0.05).Moreover,the effectof CCM on PT was dose-response to voltage.Theobvious effect was at higher voltage.No effect was ob-served at lower voltage.Conclusions Electric signalsdelivered during the absolute refractory period canrapidly enhance the contractility of myocardium,whichsuggests that CCM signal is a novel potent method forcontractility modulation.
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分类号：R54(心脏、血管（循环系）疾病)
论文发表日期：2002-07-02
在线出版日期：2025-08-15（本平台首次上网日期，不代表文献的发表时间）
页数：3( 115-117 )
英文信息