Goodman G, Bercovich D
Galil Genetic Analysis, Kazerin 12900, Israel.
J Integr Neurosci. 2013 Dec;12(4):475-89. doi: 10.1142/S0219635213500295. Epub 2013 Nov 15.
Two concepts have long dominated vertebrate nerve electrophysiology: (a) Schwann cell-formed myelin sheaths separated by minute non-myelinated nodal gaps and spiraling around axons of peripheral motor nerves reduce current leakage during propagation of trains of axon action potentials; (b) "jumping" by action potentials between successive nodes greatly increases signal conduction velocity. Long-held and more recent assumptions and issues underlying those concepts have been obscured by research emphasis on axon-sheath biochemical symbiosis and nerve regeneration. We hypothesize: mutual electromagnetic induction in the axon-glial sheath association, is fundamental in signal conduction in peripheral and central myelinated axons, explains the g-ratio and is relevant to animal navigation.
长期以来,有两个概念主导着脊椎动物神经电生理学:(a) 施万细胞形成的髓鞘由微小的无髓鞘节点间隙隔开,并围绕外周运动神经的轴突呈螺旋状排列,可减少轴突动作电位序列传播过程中的电流泄漏;(b) 动作电位在连续节点之间的“跳跃”极大地提高了信号传导速度。长期以来以及最近关于这些概念的假设和问题,都因对轴突-髓鞘生化共生和神经再生的研究重点而变得模糊不清。我们假设:轴突-胶质鞘关联中的相互电磁感应,是外周和中枢有髓轴突信号传导的基础,解释了g值比,并且与动物导航相关。