gated ion channelmedical dictionary

<physiology> Transmembrane proteins of excitable cells, that allow a flux of ions to pass only under defined circumstances. Channels may be either voltage gated, such as the sodium channel of neurones or ligand gated such as the acetylcholine receptor of cholinergic synapses. Channels tend to be relatively ion specific and allow fluxes of typically 1000 ions to pass in around 1ms, they are thus much faster at moving ions across a membrane than transport ATPases.

(05 May 1997)