- 作者: Yi-Jen Chen Yao-Chang Chen Paul Chan Cheng-I. Lin Shih-Ann Chen
- 作者服務機構: Institutes of Pharmacology and Physiology, Department of Biomedical Engineering, National Defense Medical Center, Taipei Medical University, Wan-Fang Hospital and Cardiovascular Research Center, National Yang-Ming University School of Medicine, Division of Cardiology, Veterans General Hospital-Taipei, Taipei, Taiwan
- 中文摘要: --
- 英文摘要: Temperature plays an important role in the electrophys-iology of cardiomyocytes.Pulmonary veins(PVs) areknown to initiate paroxysmal atrial fibrillation.The ef-fects of temperature on the arrhythmogenic activity ofrabbit single PV and atrial cardiomyocytes were as-sessed using the whole-cell clamp technique.PV cardio-myocytes had different beating rates at low(22-25“C),normal(38-39“C)and high(40-41“C) temperatures(0.9士0.1,3.2士0.4, 6.4士0.6 Hz, respectively; p<0.001).There were different action potential durations and inci-dences of delayed afterdepolarization in PV cardiomyo-cytes with pacemaker activity (31,59,63%;p<0.05),PVcardiomyocytes without pacemaker activity(16,47,60%;p<0.001),and atrial myocytes (0, 0, 21%:p<0.05).How-ever, oscillatory afterpotentials were only found in PVcardiomyocytes with pacemaker activity at normal(50%)or high(68%)temperatures, but not at low temperatures(p<0.001).Both PV and atrial cardiomyocytes had largertransient inward currents and inward rectified currents athigh temperatures. Additionally, PV cardiomyocyteswith and without pacemaker activity had larger pace-maker currents at higher temperatures.This study dem-onstrated that PV cardiomyocytes have an increase inarrhythmogenic activity at high temperatures because ofenhanced automaticity, induced triggered activity, orshortening of action potential duration.
- 中文關鍵字: --
- 英文關鍵字: Action potential. Atrial fibrillation. Triggered activity