醛固酮对心肌细胞钙稳态及电生理特性的影响

Effects of aldosterone on calcium homeostasis and electrophysiological features on cardiocytes

目的:探讨醛固酮致心律失常机制与钙稳态失调的关系。方法:分离心室肌细胞,随机分为对照组和醛固酮组,采用全细胞膜片钳记录方法记录延迟后除极(DAD)、触发活动,共聚焦显微镜记录钙火花。结果:醛固酮组发生DAD为24/30,对照组为7/30,P<0.05;对照组发生触发活动为5/30,醛固酮组为20/30,P<0.05。钙火花的空间范围:对照组为(0.011±0.001)s-1.m,醛固酮组为(0.024±0.001)s-1.m,P<0.05;钙火花幅度:对照组为(1.03±0.07)F/F0,醛固酮组为(1.46±0.10)F/F0,P<0.05。钙火花持续时间:醛固酮组为(7.0±0.9)ms,对照组为(13.0±1.2)ms,P<0.05。结论:醛固酮可能通过调节胞内钙产生促心律失常作用。

Objective：To investigate the effect of aldosterone on calcium homeostasis and electrophysiological features on cardiocytes.Method：Single ventricular myocytes were isolated by enzymatic dissociation method.Isolated adult rat ventricular myocytes exposed for 48 hours to aldosterone 100 nmol/L,delayed after depolarizations（DAD） and triggered activity were recorded by using whole cell patch clamp technique.Calcium spark were recorded by using confocal microscopy.Result： An increase in the occurrence of DAD and triggered activity during action potential recordings were presented in aldosterone group.The frequency of DAD was 24/30 in aldosterone group and 7/30 in control group.The occurrence and redistribution to long-lasting and broader populations of spontaneous calcium sparks increased.Conclusion：Aldosterone may be disturb calcium homeostasis on cardiocytes which contributes to cardiac arrhythmia.