depolarization

A process of excitable cells whereby a polarized cell or fiber loses its potential difference (charge) across a semipermeable membrane. Depolarization of neurons may be associated with an action potential. The depolarization is generally due to opening of Na⁺ channels with influx of Na⁺ ions. Ca⁺² channels may also be associated with depolarization.

References

Stedman's Medical Dictionary 27th ed, Williams & Wilkins, Baltimore, 1999