Recording action potentials using voltage-sensitive dyes
Recording action potentials using voltage-sensitive dyes
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DOI：
10.1007/3-540-26574-0_14
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发表时间：
2005-01-01
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影响因子：
--
通讯作者：
Fast, VG
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文献类型：
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作者：
Fast, VG
心脏的同步收缩取决于电脉冲的规律传播，其通过细胞动作电位的产生以及兴奋细胞和静息细胞之间的局部电流流动来维持（Kleber等人，2001）。正常传播模式的改变导致心律失常和收缩功能丧失。了解这些心律失常的机制依赖于使用标测技术的激活扩散的可视化，该标测技术涉及多个部位的电生理参数的测量及其分布模式的重建。目前使用两种主要的心脏标测方法。第一种标测方法是在近一百年前引入的，并在世纪的最后25年得到完善，该方法涉及使用金属电极阵列记录细胞外电位（Frazier et al. 1988）。该方法的主要应用是测量局部激活时间和重构激活序列。此外，它还用于测量除颤电击过程中细胞外电位的分布（Wharton等人，1992）。虽然有人试图将这种技术扩展到使用微电极或抽吸电极阵列来绘制跨膜电位（Vm），但事实证明，同时记录来自多个点的动作电位是困难的。由于这些原因，最近的跨膜电位映射的尝试集中在光学方法上，光学映射是基于用电压敏感染料染色心脏组织和使用光电探测器记录光学染料性质的变化。这种方法的一个重要优点是，它允许同时非接触登记的动作电位从多个紧密相邻的网站。以这种方式，除了激活模式之外，还可以监测复极模式。光学标测报告Vm变化的能力对于除颤研究特别有利，其中常规电记录受到电击诱发的伪影的阻碍。
Synchronous contraction of the heart depends on regular propagation of the electrical impulse, which is maintained by generation of cellular action potentials and by flow of local electrical currents between excited and resting cells (Kleber et al. 2001). Alterations in the normal pattern of propagation lead to arrhythmias and loss of contractile function. Understanding the mechanisms of these arrhythmias has relied on visualization of activation spread using mapping techniques that involve measurements of electrophysiological parameters at multiple sites and reconstruction of their distribution patterns. Two main cardiac mapping methods are currently used. The first mapping method introduced almost a hundred years ago and perfected in the last quarter of the 20th century involves registration of extracellular potentials using arrays of metal electrodes (Frazier et al. 1988). The main application of this method is measurement of local activation times and reconstruction of the activation sequence. In addition, it is used to measure distributions of extracellular potentials during application of defibrillation shocks (Wharton et al. 1992). Although there were attempts to extend this technique to mapping transmembrane potentials (Vm) using arrays of microelectrodes or suction electrodes, simultaneous registration of action potentials from more than several points proved to be difficult. For these reasons, more recent attempts to map transmembrane potential concentrated on optical approaches.Optical mapping is based on staining cardiac tissue with voltage-sensitive dyes and registration of changes in optical dye properties using photodetectors. One of the important advantages of this approach is that it allows simultaneous non-contact registration of action potentials from multiple closely adjacent sites. In this way, patterns of repolarization can be monitored in addition to patterns of activation. The ability of optical mapping to report Vm changes is especially advantageous for studies of defibrillation where conventional electrical recordings are hampered by shockinduced artefacts.