In normal coronary arteries, several different mechanisms of blood flow regulation exist, acting at different levels of the coronary tree: endothelial, nervous, myogenic and metabolic regulation. In addition, physiologic blood flow regulation is also dependent on the activity of several coronary ion channels, including ATP-dependent K(+) channels, voltage-gated K(+) channels and others. In this context, ion channels contribute by matching demands for homeostatic maintenance. They play a primary role in rapid response of both endothelium and vascular smooth muscle cells of larger and smaller arterial vessels of the coronary bed, leading to coronary vasodilation. Consequently, an alteration in ion channel function or expression could be directly involved in coronary vasomotion dysfunction.