Ärritusmembraan

Ärritusmembraan refers to a cellular membrane that exhibits excitability. This excitability means the membrane can undergo rapid changes in its electrical potential in response to a stimulus. Such membranes are crucial for the function of excitable cells, including neurons and muscle cells. The primary mechanism behind the excitability of these membranes is the presence of voltage-gated ion channels. These channels are proteins embedded within the membrane that can open or close in response to changes in the electrical potential across the membrane.

When a stimulus, such as a neurotransmitter or a mechanical force, is applied to an ärritusmembraan, it can cause a local depolarization. If this depolarization reaches a certain threshold, it triggers the opening of voltage-gated sodium channels. The influx of sodium ions further depolarizes the membrane, leading to a rapid and self-propagating action potential. This action potential is the fundamental electrical signal used by nerve cells to transmit information and by muscle cells to initiate contraction. Following the depolarization phase, voltage-gated potassium channels open, allowing potassium ions to flow out of the cell, repolarizing the membrane and returning it to its resting potential. The coordinated action of these ion channels allows the ärritusmembraan to generate and conduct electrical signals efficiently.