SPECTRA OF G RATIO, MYELIN SHEATH THICKNESS, AND AXON AND FIBER DIAMETER IN THE GUINEA-PIG OPTIC-NERVE
SPECTRA OF G RATIO, MYELIN SHEATH THICKNESS, AND AXON AND FIBER DIAMETER IN THE GUINEA-PIG OPTIC-NERVE
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DOI：
10.1002/cne.902870404
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发表时间：
1989-09-22
影响因子：
2.5
通讯作者：
HOPE, GM
中科院分区：
文献类型：
--
作者：
GUY, J;ELLIS, EA;HOPE, GM
对广泛应用于脱髓鞘实验障碍研究的13株豚鼠视神经纤维和轴突直径、髓鞘厚度、纤维密度和g比值的光谱进行了分析。我们对正常豚鼠视神经的详细分析研究为比较疾病状态和其他物种的形态提供了基础。与大鼠、小鼠和花栗鼠一样，豚鼠的纤维直径是单峰的，但与猫和灵长类动物的三峰纤维光谱不同。中型纤维（0.80-2.00 .mu）占优势。M)是大多数树种常见的，对平均纤维直径较大（1.45 .mu）有贡献。M)的豚鼠视神经，其中小纤维(0.50 .mu。M或更少)很少，纤维大于5.00 .mu。在猫和灵长类动物中看到的直径为M的缺失。尽管与其他物种一样，豚鼠的髓鞘厚度随着轴突直径的增加而增加，但豚鼠的g比为0.81，高于大多数哺乳动物。由于传导速度与轴突大小和髓磷脂性质有关，因此豚鼠视神经的平均轴突直径相对较大（1.18 .mu）。M)可以弥补髓鞘形成的减少。
The spectra of fiber and axon diameter, myelin sheath thickness, fiber density, and g ratio of the optic nerve were analyzed for the strain-13 guinea pig, an animal extensively utilized in the investigation of experimental disorders of demyelination. Our detailed analytical study of the normal guinea pig optic nerve provides the basis for comparison to disease states and the morphology of other species. As in the rat, mouse, and chipmunk, fiber diameters in the guinea pig were unimodal, but dissimilar to the trimodal fiber spectra of the cat and primate. The predominance of medium-size fibers (0.80-2.00 .mu.m), common to most species, contributed to the larger mean fibers diameter (1.45 .mu.m) of the guinea pig optic nerve, in which small fibers (0.50 .mu.m or less) were infrequent and fibers larger than 5.00 .mu.m in diameter, seen in the cat and primate, were absent. While myelin sheath thickness increased with axon diameter in the guinea pig, as in other species, a g ratio of 0.81 in the guinea pig was greater than in most mammals. Since conduction velocity is dependent of axon size, as well as myelin properties, the relatively larger mean axon diameter of the guinea pig optic nerve (1.18 .mu.m) may compensate for the decrease in its myelination.