Tomlinson Susan E, Hanna Michael G, Kullmann Dimitri M, Tan S Veronica, Burke David
Institute of Clinical Neurosciences, Royal Prince Alfred Hospital and University of Sydney, Sydney, Australia.
Clin Neurophysiol. 2009 Oct;120(10):1768-76. doi: 10.1016/j.clinph.2009.07.003. Epub 2009 Sep 5.
Clinical neurophysiology has become an invaluable tool in the diagnosis of muscle channelopathies, but the situation is less clear cut with neuronal channelopathies. The genetic episodic ataxias are a group of disorders with heterogeneous phenotype and genotype, but share in common the feature of intermittent cerebellar dysfunction. Episodic ataxia (EA) types 1 and 2 are the most widely recognised of the autosomal dominant episodic ataxias and are caused by dysfunction of neuronal voltage-gated ion channels. There are central and peripheral nervous system manifestations in both conditions, and they are therefore good models of neuronal channelopathies to study neurophysiologically. To date most work has focussed upon characterising the electrophysiological properties of mutant channels in vitro. This review summarises the role of voltage-gated potassium and calcium channels, mutations of which underlie the main types of episodic ataxia types 1 and 2. The clinical, genetic and electrophysiological features of EA1 and EA2 are outlined, and a protocol for the assessment of these patients is proposed.
临床神经生理学已成为诊断肌肉通道病的一项宝贵工具，但对于神经元通道病，情况则不那么明确。遗传性发作性共济失调是一组具有异质性表型和基因型的疾病，但都具有间歇性小脑功能障碍这一共同特征。发作性共济失调（EA）1型和2型是常染色体显性发作性共济失调中最广为人知的类型，由神经元电压门控离子通道功能障碍引起。这两种情况都有中枢和外周神经系统表现，因此是从神经生理学角度研究神经元通道病的良好模型。迄今为止，大多数工作都集中在体外表征突变通道的电生理特性。本综述总结了电压门控钾通道和钙通道的作用，这两种通道的突变是发作性共济失调1型和2型主要类型的基础。概述了EA1和EA2的临床、遗传和电生理特征，并提出了评估这些患者的方案。
