Halter J A, Clark J W
Division of Restorative Neurology and Human Neurobiology, Baylor College of Medicine, Houston, Texas 77030.
Neuroreport. 1993 Jan;4(1):89-92. doi: 10.1097/00001756-199301000-00023.
Myelinated nerve fibers exhibit a complex anatomy in the nodal region which includes a marked nodal-paranodal constriction and an intricate paranodal structure where the myelin sheath is separated from the axon by a narrow periaxonal space. In this study, a recently developed computational model of the mammalian myelinated nerve fiber based on electron microscopic data was employed to examine the effect of the nodal-paranodal axonal radius and periaxonal space width on the conduction of action potentials. These findings indicate that the nodal-paranodal constriction promotes higher conduction velocities by minimizing the component of the nodal capacity contributed by the paranodal axolemma. Model prediction of optimal nodal-paranodal radii is correlated with radii determined in experimental anatomical studies.
有髓神经纤维在结区呈现出复杂的解剖结构，其中包括明显的结旁结收缩以及复杂的结旁结构，在该结构中，髓鞘通过狭窄的轴周间隙与轴突分离。在本研究中，基于电子显微镜数据的哺乳动物有髓神经纤维的最新计算模型被用于研究结旁轴突半径和轴周间隙宽度对动作电位传导的影响。这些发现表明，结旁结收缩通过最小化结旁轴膜对结电容的贡献来促进更高的传导速度。最佳结旁半径的模型预测与实验解剖学研究中确定的半径相关。
