Lehmann-Horn F, Iaizzo P A, Hatt H, Franke C
Neurologische Klinik, Technischen Universität München, Federal Republic of Germany.
Pflugers Arch. 1991 Apr;418(3):297-9. doi: 10.1007/BF00370530.
Electrophysiological studies on muscle fibres from patients with hyperkalemic periodic paralysis with myotonia have shown that the episodes of weakness are caused by a sustained depolarization of the sarcolemma to potentials between -40 and -60 mV. In muscle fibre segments from three such patients this sustained depolarization was caused by noninactivating Na+ channels with reduced single-channel conductance blocked by TTX and procainamide. As the chloride conductance was normal, myotonia may be best explained with the abnormal reopenings of the Na+ channels. The recently described genetic linkage between hyperkalemic periodic paralysis with myotonia and the gene coding for the TTX-sensitive Na+ channel suggests an altered primary structure of this channel causing its abnormal function.
对患有高钾性周期性麻痹合并肌强直患者的肌纤维进行的电生理研究表明，肌无力发作是由肌膜持续去极化至-40至-60 mV之间的电位所致。在三位此类患者的肌纤维节段中，这种持续去极化是由单通道电导降低的非失活钠通道引起的，这些通道可被河豚毒素（TTX）和普鲁卡因胺阻断。由于氯电导正常，肌强直最好用钠通道的异常重新开放来解释。最近描述的高钾性周期性麻痹合并肌强直与编码TTX敏感钠通道的基因之间的遗传连锁表明，该通道一级结构的改变导致其功能异常。
