LOCAL-CONTROL OF AXONAL PROPERTIES BY SCHWANN-CELLS - NEUROFILAMENTS AND AXONAL-TRANSPORT IN HOMOLOGOUS AND HETEROLOGOUS NERVE GRAFTS
LOCAL-CONTROL OF AXONAL PROPERTIES BY SCHWANN-CELLS - NEUROFILAMENTS AND AXONAL-TRANSPORT IN HOMOLOGOUS AND HETEROLOGOUS NERVE GRAFTS
复制标题
DOI：
10.1002/jnr.490300121
复制
发表时间：
1991-09-01
影响因子：
4.2
通讯作者：
BRADY, ST
中科院分区：
文献类型：
--
作者：
DEWAEGH, SM;BRADY, ST
许多轴突特性，包括缓慢的轴突运输和神经细丝磷酸化，在雪旺细胞缺乏的突变小鼠品系中发生了改变，这种突变小鼠称为颤抖者。颤抖表型与周围神经系统髓鞘形成不良和轴突口径减少有关，但遗传损害尚未确定。为了确定轴突性质的改变是否是雪旺细胞对轴突的直接作用所致，将髓鞘缺陷颤抖鼠的一段坐骨神经移植到正常小鼠的坐骨神经中，并允许正常轴突再生。被震颤的雪旺细胞包围的正常轴突直径减小，但在移植物远端恢复其原始直径。震颤器移植到正常神经后，坐骨神经的神经丝运输也受到局部影响。在震颤器移植物的神经近端部分，神经丝运输速度与对照组没有显著差异，但进入颤颤器移植物后神经丝运输率降低。在颤抖移植物的情况下，伴随着神经细丝与微管蛋白比率的增加，这表明神经细丝减慢和微管蛋白运输的速度增加。使用颤动神经节段的异种移植到野生型神经，雪旺细胞被证明局部影响轴突口径、神经丝组织和缓慢的轴突运输。这些观察强调了神经胶质细胞在调节神经元结构和功能中的重要性，以及关注神经胶质细胞在改变神经环境的神经病理病因学中的作用。
A number of axonal properties, including slow axonal transport and neurofilament phosphorylation, are altered in a mutant mouse strain with a Schwann cell deficiency, the Trembler. The Trembler phenotype is associated with poor myelination and reduced axonal caliber in the peripheral nervous system, but the genetic lesion has not yet been identified. To determine whether changes in axonal properties resulted from a direct action of Schwann cells on the axon, a segment of sciatic nerve from myelin-deficient Trembler mouse was grafted into the sciatic nerve of a normal mouse and normal axons were allowed to regenerate. Normal axons surrounded by Trembler Schwann cells are reduced in diameter, but resume their original diameter distal to the graft. Neurofilament transport was also affected locally in sciatic nerves with Trembler grafts into normal nerve. The velocity of neurofilament transport was not significantly different from controls in portions of the nerve proximal to the Trembler graft, but there was a reduction in neurofilament transport rates upon entering the Trembler graft. This was accompanied by an increase in the ratio of neurofilament over tubulin in the case of the Trembler graft, suggesting both a slowing of the neurofilament and an increase in the rate of tubulin transport. Using heterologous grafts of Trembler nerve segments into wildtype nerves, Schwann cells were shown to locally influence axonal caliber, neurofilament organization, and slow axonal transport. These observations emphasize the importance of glial cells in modulating neuronal structure and functions, as well as focusing attention on the role of glia in the etiology of neuropathologies that alter the neuronal environment.