Repolarization

Repolarization is a term used in cell physiology and refers to the return of the membrane potential of an axon to the resting potential after a depolarization.

After depolarization of the voltage-activated sodium channels will be initially again by closing Inaktivierungstoren impermeable to sodium ions, thereby causing a further increase in the membrane potential.

In the axon membrane are also voltage-activated potassium channels, which open now. This leads - following the concentration gradient - a strong outflow of potassium ions. Thus, the external medium is enriched again with positive charge carriers, while they decrease in the interior. Consequently the membrane potential decreases again and returns after a brief hyperpolarization back to the resting potential.

The initial distribution of the ions rest potential ( outside many sodium ions and potassium ions inside many ) is then recovered by the sodium-potassium pump and the activation gates of the voltage -gated sodium channels are also closed.

Re action potential can be initiated again until the Inaktivierungstore the voltage-dependent sodium channels are opened again. This refractory period is normally about 2 ms.

• Neurophysiology
• Biophysics