England J D, Happel L T, Liu Z P, Thouron C L, Kline D G
Department of Neurology, Louisiana State University School of Medicine, New Orleans 70112-2822, USA.
Neurosci Lett. 1998 Oct 9;255(1):37-40. doi: 10.1016/s0304-3940(98)00635-1.
Twenty-seven human traumatic neuromas were examined immunocytochemically using highly specific antibodies directed against the voltage-gated delayed-rectifier potassium channel, Kv1.1. Normal sural nerves from six of the above-noted patients served as control specimens. Additionally, nine of the neuromas and two of the sural nerves were immunostained for voltage-gated calcium channels using an antibody that reacts with a wide spectrum of calcium channels. Normal myelinated fibers showed Kv1.1 specific immunoreactivity only at the juxtaparanodal regions. In contrast, within the neuromas approximately 30% of the myelinated fibers exhibited Kv1.1 specific immunoreactivity in dense patches along internodal axonal regions. The clustering of Kv1.1 channels along myelin-ensheathed internodal segments of axon was highly specific for the neuromas, and was never seen in normal nerve. Specific calcium channel immunoreactivity was not detectable in either the neuromas or sural nerves. Taken together with prior studies on sodium channels, these results suggest that selective and specific mechanisms control the distribution of ion channels within neuromas. Further investigation of ion channel changes within neuromas should provide a better understanding of the abnormal axonal hyperexcitability that frequently develops after nerve injury.
使用针对电压门控延迟整流钾通道Kv1.1的高特异性抗体，对27例人类创伤性神经瘤进行了免疫细胞化学检查。上述6例患者的正常腓肠神经作为对照标本。此外，使用与多种钙通道反应的抗体，对9例神经瘤和2例腓肠神经进行了电压门控钙通道免疫染色。正常有髓纤维仅在近结旁区域显示Kv1.1特异性免疫反应性。相比之下，在神经瘤内，约30%的有髓纤维在节间轴突区域的密集斑块中表现出Kv1.1特异性免疫反应性。Kv1.1通道沿髓鞘包裹的轴突节间段的聚集对神经瘤具有高度特异性，在正常神经中从未见过。在神经瘤或腓肠神经中均未检测到特异性钙通道免疫反应性。结合先前关于钠通道的研究，这些结果表明，选择性和特异性机制控制着神经瘤内离子通道的分布。对神经瘤内离子通道变化的进一步研究应能更好地理解神经损伤后经常出现的异常轴突过度兴奋性。
