Calcium Channels, Calcium Channel Antagonists and the Functioning of the Gastrointestinal Tract

Calcium ions play an essential role in the generation of motor activity of the gastrointestinal tract. Calcium ions enter gastrointestinal smooth muscle cells to activate contractile proteins through voltage-activated ion channels, through ion channels opened by activation of plasma membrane receptors and through release from internal stores. The pharmacology of these pathways is under intense investigation. However, at the moment only drugs that affect voltage dependent calcium channels have reached clinical significance.