Behse F, Buchthal F, Carlsen F, Knappeis G G
Brain. 1975 Sep;98(3):493-510. doi: 10.1093/brain/98.3.493.
Electron micrographs of 45 sural nerves from patients with acquired (22) or heredodegenerative neuropathy (23) were analysed with respect to the number of unmyelinated nerve fibres, 37 nerves with respect to the number of Schwann cell sub-units and of structures connected with Schwann cells. Findings were compared with those in 6 nerves from control subjects and referred to the total number rather than to the number per mm2 to eliminate error due to increase in the transverse endoneurial area, present in more than half the diseased nerves. Ninety-one per cent of the diseased nerves showed one or several abnormalities in unmyelinated fibres of their Schwann cells. The best indicator of fibre loss was an increase in the number of Schwann cell sub-units devoid of axons, found in more than half the nerves. This was the only abnormality related with decrease in number of myelinated fibres. The increase in number of empty Schwann cell sub-units was due both to loss of unmyelinated nerve fibres and to proliferation of Schwann cells. Proliferation was indicated by the higher incidence of Schwann cell nuclei in cross-sections of diseased nerves than in controls. The earliest sign of involvement was an increase in number of profiles and of small isolated Schwann cell projections, observed in 33 of 37 diseased nerves, as the only abnormality in 7 nerves. The number of unmyelinated nerve fibres by itself was of little value to indicate loss of fibres, since regeneration often replaced or more than replaced degenerated fibres. Regeneration was indicated by an increase in number or incidence of small unmyelinated fibres, present in nearly half of 45 diseased nerves; and by an increased in the total number, present in a third of the nerves. An increase in the number of collagen pockets and of fibres undergoing degeneration (loss of organelles) and a decrease in the number of unmyelinated fibres per Schwann cell sub-units was present in only a quarter to a third of diseased nerves and was not related to other criteria of loss of fibres or of regneration.
对45例获得性（22例）或遗传性变性神经病（23例）患者的腓肠神经进行电子显微镜检查，分析无髓神经纤维数量，对37条神经分析施万细胞亚单位数量以及与施万细胞相关的结构。将结果与6例对照受试者的神经结果进行比较，并以总数而非每平方毫米数量来表示，以消除因超过半数患病神经的神经内膜横截面积增加而导致的误差。91%的患病神经在其施万细胞的无髓纤维中显示出一种或几种异常。纤维丢失的最佳指标是超过半数神经中无轴突的施万细胞亚单位数量增加。这是与有髓纤维数量减少相关的唯一异常。空的施万细胞亚单位数量增加既归因于无髓神经纤维的丢失，也归因于施万细胞的增殖。患病神经横切面中施万细胞核的发生率高于对照组，这表明了增殖现象。受累的最早迹象是在37条患病神经中的33条中观察到轮廓数量和孤立的小施万细胞突起数量增加，在7条神经中这是唯一的异常。无髓神经纤维自身数量对于指示纤维丢失价值不大，因为再生常常替代或超过替代退化的纤维。再生表现为在45条患病神经中近半数存在的小无髓纤维数量或发生率增加；以及在三分之一的神经中总数增加。胶原小囊数量和正在发生变性（细胞器丢失）的纤维数量增加以及每个施万细胞亚单位中无髓纤维数量减少仅出现在四分之一到三分之一的患病神经中，并且与纤维丢失或再生的其他标准无关。
