Heme oxygenase, carbon monoxide, and interstitial cells of Cajal

Interstitial cells of Cajal play a central role in the control of gastrointestinal motility. The mechanisms of communication between interstitial cells of Cajal and smooth muscle cells are to a large extent unknown. This article reviews the potential role of carbon monoxide as a messenger molecule between interstitial cells of Cajal and gastrointestinal smooth muscle cells. The machinery required for the formation of carbon monoxide is present in interstitial cells of Cajal and gastrointestinal smooth muscle cells express a target site of action for carbon monoxide, a potassium channel. Carbon monoxide may, therefore, be produced in interstitial cells of Cajal and function as a messenger molecule between interstitial cells of Cajal and gastrointestinal smooth muscle cells.