快速电场起搏对心房肌细胞电生理特性的实验研究

Study of rapid pacing-Induced electrical remodeling in cultured neonatal rat atrial myocytes

目的利用原代培养的心房肌细胞建立快速电场起搏模型,对其电生理特性进行初步研究。方法原代培养大鼠心房肌细胞,建立快速起搏的细胞模型,利用全细胞膜片钳技术检测起搏前、后的动作电位周期和有效不应期变化。结果成功建立了原代心房肌细胞的快速起搏模型,细胞纯度符合实验要求。快速电场起搏6 h后心房肌细胞的APD50和ERP较起搏前无显著变化,APD90较起搏前显著缩短(P<0.05)。快速电场起搏后12、24和48 h后心房肌细胞的APD50和APD90均较起搏前显著缩短(P<0.05),ERP较起搏前无显著变化。结论建立了快速起搏的房颤模型,其电生理特性符合房颤电重构的特点,为房颤的进一步深入研究奠定基础。

Objective To explore the characteristics of electrical remodeling with a rapid paced primary cultured atrial myocyte model for atrial fibrillation.Methods Primary rat atrial myocytes were cultured and a rapid paced primary cultured atrial myocyte model was established.Action potential durations and effective refractory periods were recorded from stimulated cells,as well as control cells cultured with the whole-cell voltage-clamp techniques.Results Immunocytochemical analysis showed that over 90 percent of cells were stained positively for a-actin,a factor specific for cardiomyocytes.The action potential duration was shortened through the rapid pacing compared with those before pacing（P0.05）.There was no significant difference in effective refractory periods after pacing compared with that before pacing.Conclusion Rapid pacing of cultured atrial myocytes produces electrical remodeling.The electrical characteristics of atrial myocytes are similar with that in atrial fibrillation.It is considered that the rapid paced cell model of atrial myocytes can be used to study the mechanism for atrial fibrillation.