Clancy Colleen E, Kass Robert S
Department of Physiology and Biophysics, Institute for Computational Biomedicine, Weill Medical College of Cornell University, New York, New York 10021, USA.
Physiol Rev. 2005 Jan;85(1):33-47. doi: 10.1152/physrev.00005.2004.
Mutations in cardiac Na(+) and K(+) channels can disrupt the precise balance of ionic currents that underlies normal cardiac excitation and relaxation. Disruption of this equilibrium can result in arrhythmogenic phenotypes leading to syncope, seizures, and sudden cardiac death. Congenital defects result in an unpredictable expression of phenotypes with variable penetrance, even within single families. Additionally, phenotypically opposite and overlapping cardiac arrhythmogenic syndromes can stem from one mutation. A number of these defects have been characterized experimentally with the aim of understanding mechanisms of mutation-induced arrhythmia. Improving understanding of abnormalities may provide a basis for the development of therapeutic approaches.
心脏钠（Na⁺）通道和钾（K⁺）通道的突变会破坏构成正常心脏兴奋和舒张基础的离子电流的精确平衡。这种平衡的破坏会导致致心律失常表型，进而引发晕厥、癫痫发作和心源性猝死。先天性缺陷会导致具有可变外显率的表型出现不可预测的表达，即使在单个家族中也是如此。此外，表型相反和重叠的心脏致心律失常综合征可能源于同一个突变。为了理解突变诱导的心律失常机制，已经对其中一些缺陷进行了实验表征。增进对异常情况的了解可能为治疗方法的开发提供基础。
