Calcium (Ca) is a universal intracellular second messenger. In muscle, Ca is best known for its role in contractile activation. However, in recent years the critical role of Ca in other myocyte processes has become increasingly clear. This review focuses on Ca signaling in cardiac myocytes as pertaining to electrophysiology (including action potentials and arrhythmias), excitation-contraction coupling, modulation of contractile function, energy supply-demand balance (including mitochondrial function), cell death, and transcription regulation. Importantly, although such diverse Ca-dependent regulations occur simultaneously in a cell, the cell can distinguish distinct signals by local Ca or protein complexes and differential Ca signal integration.

中文翻译：

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心肌细胞中的钙循环和信号传导。

钙 (Ca) 是一种通用的细胞内第二信使。在肌肉中，Ca 以其在收缩激活中的作用而闻名。然而，近年来，Ca 在其他肌细胞过程中的关键作用变得越来越清楚。本综述重点关注心肌细胞中的 Ca 信号传导，涉及电生理学（包括动作电位和心律失常）、兴奋-收缩耦合、收缩功能的调节、能量供需平衡（包括线粒体功能）、细胞死亡和转录调节。重要的是，虽然这种不同的 Ca 依赖性调节同时发生在一个细胞中，但细胞可以通过局部 Ca 或蛋白质复合物以及差异 Ca 信号整合来区分不同的信号。