Repolarisation

Part of speech: noun

Definitions

1. The process by which a cell membrane restores its resting electrical state after depolarisation in nerve or muscle cells ; the phase in an action potential where ions move to re-establish the negative internal charge ; the restoration of the original polarization following excitation in excitable tissues
2. Restoration of the electrical polarity of a cell membrane by returning ion distribution to baseline after a depolarising event ; the stage where voltage-gated channels close and membrane potential normalizes in neurons or cardiac cells ; the return to baseline electrical charge after a cellular activation phase
3. The cellular mechanism that returns an excitable cell to its resting negative charge after it has been activated ; the movement of ions, such as potassium out of the cell, which resets membrane voltage ; the phase in which a previously depolarised membrane changes back to its polarized state in biological cells

Etymology: "Repolarisation" is a straightforward formation: the prefix "re-", meaning "again" or "back to a former state," attached to "polarisation." The base word "polarisation" comes from "polarise," which in turn is built on "polar," from Latin "polaris," relating to the pole. In physical and biological contexts, polarisation describes a separation of electrical charge across a surface or membrane. Repolarisation, then, is the process by which that separation is restored after it has been temporarily lost. The most familiar setting is the nerve cell. When a neuron fires, its membrane briefly reverses its charge, and the cell must return to its resting state before it can fire again. That return is repolarisation, and it is what lets a nerve signal be passed along in a controlled, one-directional sequence rather than flickering back and forth.

Synonyms: repolarization, restoration, recharging, resetting, recovery

Antonyms: depolarization, discharge, disruption