Sharma A K, Thomas P K, Baker R W
J Neurol Neurosurg Psychiatry. 1976 Aug;39(8):794-802. doi: 10.1136/jnnp.39.8.794.
Electrophysiological, biochemical, and morphometric observations were made on the peripheral nerves of rats after galactose feeding. Motor nerve conduction velocity was found to be reduced. This was associated with an accumulation of galactitol in the peripheral nerves and a diminution in their myoinositol content. An increased water content and fascicular area, taken in conjunction with a probable increase in the area of the endoneurial spaces, indicated overhydration of the peripheral nerves. Morphometric observations on the myelinated fibre population in the tibial nerve showed no loss of fibres and although both the maximal and the average diameter of the myelinated fibres was slightly less than in age-matched controls, this was insufficient to explain the reduction in conduction velocity. Segmental demyelination was not detected and the relationship between myelin thickness and axon circumference was not altered. Electron microscope observations revealed no ultrastructural changes in the myelinated fibres and, in particular, no abnormalities at the nodes of Ranvier or indication of abnormal hydration of the Schwann cells. The relevance of these findings to the peripheral nerve changes in human and experimental diabetes is discussed.
对喂食半乳糖后的大鼠外周神经进行了电生理、生化和形态学观察。发现运动神经传导速度降低。这与外周神经中半乳糖醇的积累及其肌醇含量的减少有关。水分含量和束面积增加，再加上神经内膜间隙面积可能增加，表明外周神经存在过度水化。对胫神经有髓纤维群体的形态学观察显示没有纤维丢失，尽管有髓纤维的最大直径和平均直径均略小于年龄匹配的对照组，但这不足以解释传导速度的降低。未检测到节段性脱髓鞘，髓鞘厚度与轴突周长之间的关系也未改变。电子显微镜观察显示有髓纤维没有超微结构变化，特别是郎飞结处没有异常，也没有施万细胞异常水化的迹象。讨论了这些发现与人类和实验性糖尿病外周神经变化的相关性。
