What is "axolemma"

n. The surface membrane of an axon

n. outer membrane covering an axon

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. 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. An unmyelinated axolemma has a high capacitance which imposes a restraint on the conduction speed.

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.