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Hyperpolarization

Could someone explain to me why an influx of potassium hyperpolarizes the nerve cell.

Thanks :biggrin:

Voltage gated potassium channels are slow to inactivate during the repolarisation phase, so there is a small "overshoot" where the cell potential drops below -70mV. Ie. there is an excess of K+ EFFLUX. remember the sodium ions are the ones moving into the cell, the potassium ions are moving out of the cell

Reply 2

dynamicmind

K+ is influxed brother, its called hyperpolarisation :smug:

Reply 3

inthevale

Original post by bertstare

remember the sodium ions are the ones moving into the cell, the potassium ions are moving out of the cell

A way to remember this is that the Na+ is the dominant extracellular cation, and K+ is the dominant intracellular cation and they follow the electrochemical gradients.