《中国康复理论与实践》

《中国康复理论与实践》 ›› 2006, Vol. 12 ›› Issue (08): 685-684.

• 基础研究 • 上一篇    下一篇

高胆固醇血症家兔心脏单相动作电位及钙电流的特征

高玉玲1; 马晶1; 陈玉娟1; 杨潇洋2; 李泱1   

  1. 1.解放军总医院老年心血管病研究所,北京市 100853;2.中国科学技术大学少年班系,安徽合肥市 230026
  • 收稿日期:2006-04-10 出版日期:2006-08-01 发布日期:2006-08-01

Characteristics of Monophasic Action Potential and Calcium Current of Heart in Rabbit with Hyperlipidemia

GAO Yu-ling, MAJing,CHEN Yu-juan, et al   

  1. The Institute of Geriatric Cardiology, the General Hospital of PLA, Beijing 100853, China
  • Received:2006-04-10 Published:2006-08-01 Online:2006-08-01

PDF (PC)

摘要： 目的观察高胆固醇血症对家兔心脏单相动作电位及钙电流的影响。方法24只家兔分为高胆固醇饮食组和对照组各12只,分别给予高胆固醇饲料和标准饲料饲养10周后,检测血脂、心电图和室颤阈值,记录离体灌流心脏单相动作电位,并记录心室肌细胞的L型钙通道电流。结果高胆固醇饮食组兔的血脂水平明显高于对照组(P<0.01);室颤阈值(10.2±1.7)V,低于对照组的(13.9±1.3)V(P<0.05);单相动作电位复极90%的时程(MAPD90)较对照组延长并呈更明显的逆频率依赖性,在1500ms起搏时MAPD90为(348±21)ms,而对照组为(271±16)ms;心室肌细胞的L型钙通道电流密度为(14.7±0.8)pA/pF,明显高于对照组的(10.9±1.1)pA/pF(P<0.01)。结论高胆固醇血症家兔的心脏单相动作电位及心肌细胞L型钙通道电流明显改变,复极时程延长,室颤阈值降低。

关键词: 高胆固醇血症, 家兔, 室颤阈值, 单相动作电位, 钙电流

Abstract: ObjectiveTo investigate the effect of hyperlipidemia on monophasic action potential and calcium current of heart in rabbits.Methods24 rabbits were divided into the high cholesterol group (n=12) and control group (n=12) and fed with high cholesterol forage and standard forage respectively for 10 weeks. Electrocardiograph, ventricular fibrillation threshold and the level of serum lipid were examined. Whole-cell patch clamp technique was used to record I_ Ca-L.ResultsIn high cholesterol group, the serum cholesterol level was higher than the control group ( P<0.01), ventricular fibrillation threshold (10.2±1.7 V) lower than that of the control group (13.9±1.3 V)( P<0.05), MAPD90 displayed more significant rate-dependent prolongation. At cycle lengths of 1500 ms, MAPD90 was 358±18 ms in the high cholesterol group, while it was 277±20 ms in the control group. The densities of ICa-L were larger in the high cholesterol group (14.7±0.8 pA/pF) than that in the control group (10.9±1.1 pA/pF)( P<0.01).ConclusionHypercholesterolemia can produce cardiac electrical remodeling, including increased ICa-L, prolonged repolarization and decreased ventricular fibrillation thresholds.

Key words: hypercholesterolemia, rabbit, ventricular fibrillation threshold, monophasic action potential, calcium current