Mechanism of the Action Potential Propagation
The upper panel is a plot of the membrane potential change as a function of time in milliseconds as the action potential moves down the axon. Note that the action potential moves down the axon as a wave, following the opening voltage gated channels. The lower portion of the animation illustrates what happens at the level of the axon. Click here to see a legend. The purple is the axon membrane. Embedded in the membrane are the closed, open and inactive voltage gated channels. Note that only a small fraction of the channels are open (red arrows) at any instant in time and this fraction moves down the axon and allows the membrane potential to develop behind it. Shortly after opening, the channels become inactive and remain so until the membrane repolarizes and allows the channels to return to their closed configuration. Click here to see a faster and larger version of this animation.
Click on the animation to see a larger view of the slower animation.