Definition
CNS myelin consists of many layers of tightly wound membranes formed from the cytoplasmic extensions of oligodendrocytes. Myelin forms regular patches around axons, called the internode. The space between the internodes is the Node of Ranvier. The size of the internode and the thickness of the myelin sheath depend on the diameter of the axon it is associated with. The main role of myelin is to insulate the axonal membrane and thus speed the rate of conduction of the action potential, which jumps for one node to the next, a process called saltatory conduction. Myelin also contains molecules that can inhibit axon growth and regeneration. Myelin is composed of lipids (about 70%) and proteins (about 30%) such as myelin basic proteins, myelin-associated glycoprotein, proteolipid PLP.
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© 2009 Springer-Verlag GmbH Berlin Heidelberg
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(2009). Myelin. In: Binder, M.D., Hirokawa, N., Windhorst, U. (eds) Encyclopedia of Neuroscience. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-29678-2_3695
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DOI: https://doi.org/10.1007/978-3-540-29678-2_3695
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Publisher Name: Springer, Berlin, Heidelberg
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