Stretch-activated or stretch-gated ion channels are ion channels which open their pores in response to mechanical deformation of a neuron's plasma membrane. Stretch-activated channels were first observed in chick skeletal muscles by Falguni Guharay and Frederick Sachs in 1983 and the results were published in 1984.[1] Since then strech-activated channels have been found in cells from bacteria to human as well as plants.
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One of the three main types of ionotropic receptors or channel-linked receptor, which open by transmitting physical forces of stretch or pressure to the channels, causing them to undergo a conformational change to allow ions to pass through.[2] The channels may also be pulled open due to tension on the membrane itself.[2] Opening the channels allows ions to which they are permeable to flow down their electrochemical gradients into or out of the cell, causing a change in membrane potential.
This can also be referred to as the Stress-activated gate because the gate (protein receptor) responds to pressure or stress.
Such channels are of use in the initial formation of an action potential from a mechanical stimulus, for example by the mechanoreceptors in an animal's vibrissae (whiskers).
A possible role in myoblast development has been described.[3]
Mechanically gated ion channels are also found in the stereocilia of the inner ear. Sound waves are able to bend the stereocilia and open up ion channels leading to the creation of nerve impulses.[4]
These channels also play a role in sensing vibration and pressure via activation of Pacinian corpuscles in the skin.[5]
An example is "MID-1" (also known as "MCLC" or CLCC1.)[6][7]
Other examples include, TREK-1 and TRAAK which are found in mammalian neurons and are classified as potassium channels in the tandem pore domain class.[8][9]
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