醛固酮对心肌细胞钙稳态及电生理特性的影响

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。

Effects of aldosterone on calcium homeostasis and electrophysiological features on cardiocytes

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.