Regulation of ion channels in pulmonary artery smooth muscle cells

Owning to the development of modern electrophysiological and molecular biology techniques, enormous progress in our understanding of the function, physiological significance and molecular identity of pulmonary ion channels has been made during last two decades since the first recording of the ion channel currents. This work has revealed a complexity and heterogeneity of ion channel expression in PASMCs, which depends on both the species and the site of the arterial vasculature under investigation, as well as multiple potential mechanisms for oxygen sensing by ion channels (24, 56). Therefore, the key questions in pulmonary ion physiology remain essentially the same: how does hypoxia causes HPV, which types of ion channels are involved in this process, and what is the mechanism(s) responsible for the oxygen sensitivity of ion channels involved? Since it is possible that hypoxia may not directly target the ion channels, but may alter their activity via unknown intracellular regulatory factors, the investigation of molecular mechanisms which specifically control the pulmonary ion channels, (particularly those regulating K+ and Ca2+ transport) represents an important and challenging task for the future research in the field of pulmonary electrophysiology.