Introduction to Axons at Rest
- When axons are not conducting impulses (action potentials or depolarization events), they are said to be “at rest”. Unlike the term implies, resting neurons actually expend a lot of energy (ATP) distributing ions to both sides of the axon membrane.
- Most of the ions are distributed by transporter and channel proteins embedded in the axon membrane.
- The dispersal of charged particles causes the membrane to slightly polarize.
- The intracellular fluid (ICF) becomes relatively negative compared to the extracellular fluid (ECF).
- As long as the polarized state is maintained, axons will not produce an impulse, but they are ready to do so.