Arimura Kimiyoshi, Sonoda Yoshito, Watanabe Osamu, Nagado Tatsui, Kurono Asutsugu, Tomimitsu Hisanori, Otsuka Reika, Kameyama Masaki, Osame Mitsuhiro
Third Department of Internal Medicine, Kagoshima University, 8-35-1 Sakuragaoka, Kagoshima, 890-8520, Japan.
Muscle Nerve Suppl. 2002;11:S55-8. doi: 10.1002/mus.10148.
Isaacs' syndrome (acquired neuromyotonia) is an antibody-mediated potassium channel disorder (channelopathy). The target channel proteins of the antigens are voltage-gated potassium channels (VGKCs), especially dendrotoxin-sensitive fast potassium channels. The suppression of voltage-gated outward K(+) current by antibodies induces hyperexcitability of the peripheral nerve. Patch clamp studies show that antibodies may not directly block the kinetics of VGKCs but may decrease channel density. Electrophysiological, pharmacological, and immunological findings indicate that the site of origin of spontaneous discharges is principally in the distal portion of the motor nerve and/or within the terminal arborization. The spectrum of potassium channelopathies is expanding. The existence of antibodies against VGKCs should be considered in patients who present with generalized nerve hyperexcitability of undetermined etiology.
艾萨克斯综合征（获得性神经性肌强直）是一种抗体介导的钾通道疾病（通道病）。抗原的靶通道蛋白是电压门控钾通道（VGKC），尤其是对树眼镜蛇毒素敏感的快速钾通道。抗体对电压门控外向钾电流的抑制会诱发周围神经的兴奋性过高。膜片钳研究表明，抗体可能不会直接阻断电压门控钾通道的动力学，但可能会降低通道密度。电生理、药理学和免疫学研究结果表明，自发放电的起源部位主要在运动神经的远端部分和/或终末分支内。钾通道病的范围正在扩大。对于病因不明的全身性神经兴奋性过高的患者，应考虑是否存在抗电压门控钾通道抗体。
