Axolemma

Axolemma
Identifiers
Code TH H2.00.06.1.00003

Anatomical terminology

The axolemma is the cell membrane surrounding an axon. It is responsible for maintaining the membrane potential of the neuron, and it contains ion channels through which ions can flow rapidly.[1] When this occurs, the voltage inside the axon changes, and depolarization or hyperpolarization of the membrane can occur. Adequate depolarization can lead to an action potential, which travels down the axon in a self-propagating manner as more ion channels open due to stimulation by the influx of positive ions.[2] An unmyelinated axolemma has a high capacitance which imposes a restraint on the conduction speed. . The constricted axon segment is one of the few locations in which there is ten times more schwann cell membrane than axolemma, while other portions they have equal distributions.[3]

If the axolemma is damaged, it becomes unable to perform its vital role of maintaining the concentration gradient of ions inside and outside the cell. When ions move down their concentration gradient into the cell, they can cause a number of different cellular processes that may lead to cell damage or cell death.

Axolemma is involved in preventing the hyperexcitability of gray matter axons.[1]

References

  1. 1 2 Hamada, M. S.; Kole, M. H. P. (6 May 2015). "Myelin Loss and Axonal Ion Channel Adaptations Associated with Gray Matter Neuronal Hyperexcitability". Journal of Neuroscience. 35 (18): 7272–7286. doi:10.1523/JNEUROSCI.4747-14.2015.
  2. Elaine N. Marieb and Katja Hoehn (2007). Human Anatomy & Physiology (7th ed.). Pearson. pp. 393–412. ISBN 0-8053-5909-5.
  3. Stys, edited by Stephen G. Waxman, Jeffery D. Kocsis, Peter K. (1995). The axon : structure, function, and pathophysiology. New York: Oxford University Press. p. 39. ISBN 0195082931.

External links


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