Cardiac alternans and intracellular calcium cycling.
Cardiac alternans and intracellular calcium cycling.
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心脏交替和细胞内钙循环。
DOI：
10.1111/1440-1681.12231
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发表时间：
2014-07
影响因子：
2.9
通讯作者：
Blatter LA
中科院分区：
文献类型：
--
作者：
Edwards JN;Blatter LA
心脏交替是指在恒定心率下，电活动和心肌收缩强度存在周期性搏动振荡的状况。在临床上，心脏电交替发生在心律失常的典型情况下，并与这些疾病有因果关系。在细胞水平上，交替被定义为收缩幅度（机械交替）、动作电位时程（APD;电交替或APD交替）和Ca 2+瞬时幅度（Ca 2+交替）的搏动-搏动交替。电交替的发生是多因素的，但电交替的发生往往是由于细胞膜电压（Vm）和细胞内钙离子（[Ca ~（2+）]i）之间的双向耦合受到干扰。双向偶联是指在心肌细胞中，Vm去极化和动作电位的产生引起收缩所需的[Ca 2 +]i升高（称为兴奋-收缩偶联的过程），另一方面[Ca 2 +]i的变化控制Vm，因为重要的膜电流是Ca 2+依赖性的。越来越多的证据表明，交替最终是由细胞Ca 2+信号转导的干扰引起的。在这里，我们回顾了心脏细胞Ca 2+循环的两个关键因素--从内部储存中释放Ca 2+和每次搏动后清除胞浆中Ca 2+的能力--如何决定交替发生的条件。从关键的Ca 2+处理蛋白的贡献-表面膜通道，离子泵和转运，和内部Ca 2+释放通道-进行了讨论。
Cardiac alternans refers to a condition in which there is a periodic beat-to-beat oscillation in electrical activity and the strength of cardiac muscle contraction at a constant heart rate. Clinically, cardiac alternans occurs in settings that are typical for cardiac arrhythmias and has been causally linked to these conditions. At the cellular level, alternans is defined as beat-to-beat alternations in contraction amplitude (mechanical alternans), action potential duration (APD; electrical or APD alternans), and Ca2+ transient amplitude (Ca2+ alternans). The cause of alternans is multifactorial, however alternans always originate from disturbances of the bi-directional coupling between membrane voltage (Vm) and intracellular calcium ([Ca2+]i). Bi-directional coupling refers to the fact that in cardiac cells, Vm depolarization and the generation of action potentials cause the elevation of [Ca2+]i that is required for contraction (a process referred to as excitation-contraction coupling), the changes of [Ca2+]i on the other hand control Vm because important membrane currents are Ca2+-dependent. Evidence is mounting that alternans is ultimately caused by disturbances of cellular Ca2+ signaling. Here we review how two key factors of cardiac cellular Ca2+ cycling - the release of Ca2+ from internal stores and the capability of clearing the cytosol from Ca2+ after each beat - determine the conditions under which alternans occurs. The contributions from key Ca2+ handling proteins - surface membrane channels, ion pumps and transporters, and internal Ca2+ release channels - are discussed.
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DOI：
10.1085/jgp.201210862
发表时间：
2012-08
期刊：
The Journal of general physiology
影响因子：
--
作者：
Dulhunty AF;Beard NA;Hanna AD
通讯作者：
Hanna AD
DOI：
10.1016/j.bbamcr.2011.01.030
发表时间：
2011-05-01
影响因子：
5.1
作者：
Bootman, Martin D.;Smyrnias, Ioannis;Roderick, H. Llewelyn
通讯作者：
Roderick, H. Llewelyn
影响因子：
5.5
作者：
Blatter, LA;Kockskämper, J;Lipsius, SL
通讯作者：
Lipsius, SL
影响因子：
20.1
作者：
Aistrup, Gary L.;Kelly, James E.;Wasserstrom, J. Andrew
通讯作者：
Wasserstrom, J. Andrew
影响因子：
9.7
作者：
Dibb, Katharine M.;Clarke, Jessica D.;Trafford, Andrew W.
通讯作者：
Trafford, Andrew W.