Microelectrode array measurement of potassium ion channel remodeling on the field action potential duration in rapid atrial pacing rabbits model

International Journal of Clinical and Experimental Medicine

Juan Sun¹  Ling Zhang¹  Wenli Xu¹  Yujun Guo¹  Huang Yan¹  Mei Ma¹  Najina Wugeti¹  Changan Jiao¹  Tianqi Li¹  Xingui Guo¹ 

关键词: Atrial fibrillation;    microelectrode arrays;    rapid atrial pacing;    field action potential duration;    potassium ion channel blocker;   

DOI  :  

学科分类：医学（综合）

来源: e-Century Publishing Corporation

【 摘 要 】

Background: Atrial fibrillation (AF) arises from abnormalities in atrial structure and electrical activity. Microelectrode arrays (MEA) is a real-time, nondestructive measurement of the resting and action potential signal, from myocardial cells, to the peripheral circuit of electrophysiological activity. This study examined the field action potential duration (fAPD) of the right atrial appendage (RAA) by MEA in rapid atrial pacing (RAP) in the right atrium of rabbits. In addition, this study also investigated the effect of potassium ion channel blockers on fAPD. Methods: 40 New Zealand white rabbits of either sex were randomly divided into 3 groups: 1) the control, 2) potassium ion channel blocker (TEA, 4-Ap and BaCl₂), and 3) amiodarone groups. The hearts were quickly removed and right atrial appendage sectioned (slice thickness 500 μm). Each slice was perfused with Tyrode’s solution and continuously stimulated for 30 minutes. Sections from the control group were superfused with Tyrode’s solution for 10 minutes, while the blocker groups and amiodarone were both treated with their respective compounds for 10 minutes each. The fAPD of RAA and action field action potential morphology were measured using MEA. Results: In non-pace (control) groups, fAPD was 188.33 ± 18.29 ms after Tyrode’s solution superfusion, and 173.91 ± 6.83 ms after RAP. In pace/potassium ion channel groups, TEA and BaCl₂ superfusion prolonged atrial field action potential (fAPD) (control vs blocker: 176.67 ± 8.66 ms vs 196.11 ± 10.76 ms, 182.22 ± 12.87 ms vs 191.11 ± 13.09 ms with TEA and BaCl₂ superfusion, respectively, P < 0.05). 4-AP superfusion significantly prolonged FAPD. In pace/amiodarone groups, 4-Ap superfusion extended fAPD. Conclusions: MEA was a sensitive and stable reporter for the measurement of the tissue action potential in animal heart slices. After superfusing potassium ion channel blockers, fAPD was prolonged. These results suggest that I_to, I_Kur and I_K1 remodel and mediate RAP-induced atrial electrical remodeling. Amiodarone alter potassium ion channel activity (I_to, I_Kur, I_K1 and I_Ks), shortening fAPD.

【 授权许可】

Unknown