High resolution

Module 1: Figure stimuli for ion channels

Function of ion channels as receptors for cell stimuli.

Ion channels are sensitive to a range of modalities and can thus be considered to be receptors. Unlike other receptors, they combine all of the components of the signalling pathway in a single protein. When they detect the incoming stimulus (receptor function), they undergo a conformational change (transducer function) to gate large quantities of ions (amplification function). With regard to messenger function, those receptors that gate Ca2+ contribute to Ca2+ signalling pathways. The gating of ions also changes membrane potential (∆V) and this can have a messenger function by altering the activity of voltage-operated Ca2+ channels (VOCs).