Effects of acetylcholine on electrical remodeling of human atrial fibers |
| |
Authors: | Chengkun Xia Jiahong Xia볒红 Zhigang Shui Jinping Liu Wei Sun Yimei Du Guoliang Hao |
| |
Affiliation: | 1. Department of Cardiovascular Surgery 2. Ion Channelopathy Research Center, Institute of Cardiology, Union Hospital Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China 3. Department of Biological Engineering, South-Central University for Nationalities, Wuhan 430074, China |
| |
Abstract: | Autonomic nervous system activation can result in significant changes of atrial electrophysiology and facilitate induction of atrial fibrillation. By recording influence of different concentrations of acetylcholine (ACh) on atrial fibers (AF), we investigated the role of the increased vagal tone in electrical remodeling in atrial fibrillation. Parameters of action potentials and force contraction (Fc) in atrial fibers were recorded by using standard intracellular microelectrode technique and force transducer. It was found that: (1) ACh at 0.1 μmol/L had no significant influence on spontaneous action potentials (SAPs) and Fc (n=6, P>0.05); ACh at both 1.0 and 10.0 μmol/L shortened action potential duration (APD) and Fc of human AF from right atrium (n=6, P<0.05); there was no significant difference in shortening APD between 10.0 and 1.0 μmol/L of ACh; (2) ACh at 0.1 μmol/L had no significant desensitization (n=6, P>0.05), but ACh at 1.0 and 10.0 μmol/L had desensitization (n=6, P<0.05) to SAPs and Fc. The desensitization of ACh on APD in AF was concentration- and time-dependent. It was shown that APD was longer than the control along with extending time of continuous Tyrode’s solution perfusion after desensitization. It is concluded that ACh changes the electrophysiological characteristics of human AF, indicating that increased vagal tone plays a role in the development of a vulnerable substrate for atrial electrical remodeling in atrial fibrillation. |
| |
Keywords: | electrical remodeling vagal nervous system acetylcholine desensitization |
本文献已被 CNKI 维普 万方数据 SpringerLink 等数据库收录! |
|