Dorsal Root Ganglion - Mechanosensitive Channels

Mechanosensitive Channels

The nerve endings of dorsal root ganglion neurons have a variety of sensory receptors that are activated by mechanical, thermal, chemical, and noxious stimuli. In these sensory neurons, a group of ion channels thought to be responsible for somatosensory transduction have been identified. Compression of the dorsal root ganglion by a mechanical stimulus lowers the voltage threshold needed to evoke a response and causes action potentials to be fired. This firing may even persist after the removal of the stimulus.

Two distinct types of mechanosensitive ion channels have been found in the dorsal root ganglion neurons. The two channels are broadly classified as either high-threshold (HT) or low threshold (LT) . As their names suggest, they have different thresholds as well as different sensitivities to pressure. These are cationic channels whose activity appears to be regulated by the proper functioning of the cytoskelton and cytoskeleton associated proteins. The presence of these channels in the dorsal root ganglion gives reason to believe that other sensory neurons may contain them as well.