Conradi N G, Sjöström A, Karlsson B, Sourander P
Acta Physiol Scand. 1985 Oct;125(2):277-83. doi: 10.1111/j.1748-1716.1985.tb07716.x.
The optic nerve of normal (C) and protein deprived (PD) adult rats was examined by morphometry and biochemistry. The mean cross-sectional area of the optic nerve was reduced by 15% and the number of axons per unit area increased by 17% in the PD rats. Calibre spectrum analysis of axons revealed a reduction in median diameter from 0.49 micron in controls to 0.45 micron in PD rats. The number of axons with a diameter larger than 1 micron was reduced by 35% in PD rats. These reductions were probably due to a general reduction in size, since the calculated total number of axons in the optic nerve was almost identical in C and PD rats (126 X 10(3) and 124 X 10(3), respectively). The increased packing density of axons in the nerve was not only due to thinner axons. The biochemical measurements showed a marked reduction in myelin basic protein in the optic nerves of PD rats, without an alteration in the composition of the total protein. This confirms the persistent hypomyelination which has been reported previously in other malnutrition models. The possible relations between the structural and biochemical changes affecting optic nerve fibres and physiological findings on cortical visual evoked response and on optic nerve in vitro in PD rats are discussed.
通过形态计量学和生物化学方法对正常成年大鼠（C组）和蛋白质缺乏成年大鼠（PD组）的视神经进行了检查。PD组大鼠视神经的平均横截面积减少了15%，单位面积内的轴突数量增加了17%。轴突的管径谱分析显示，中位数直径从对照组的0.49微米降至PD组的0.45微米。PD组大鼠中直径大于1微米的轴突数量减少了35%。这些减少可能是由于尺寸普遍减小所致，因为计算得出的C组和PD组大鼠视神经中轴突的总数几乎相同（分别为126×10³和124×10³）。神经中轴突堆积密度的增加不仅仅是由于轴突变细。生化测量结果显示，PD组大鼠视神经中的髓鞘碱性蛋白显著减少，而总蛋白组成没有改变。这证实了先前在其他营养不良模型中报道的持续性髓鞘形成不足。本文讨论了影响PD组大鼠视神经纤维的结构和生化变化与皮质视觉诱发电位及离体视神经生理结果之间的可能关系。
