KATP channel: relation with cell metabolism and role in the cardiovascular system

Abstract: ATP-sensitive potassium channel (KATP) is one kind of inwardly rectifying channel composed of two kinds of subunits: the pore forming subunits and the regulatory subunits. KATP channels exist in the sarcolemmal, mitochondrial and nuclear membranes of various tissues. Cell metabolism regulates KATP gene expression and metabolism products regulate the channel by direct interactions, while KATP controls membrane potentials and regulate cell activities including energy metabolism, apoptosis and gene expression. KATP channels from different cell organelles are linked by some signal molecules and they can respond to common stimulation in a coordinate way. In the cardiovascular system KATP has important functions. The most prominent is that opening of this channel can protect cardiac myocytes against ischemic injuries. The sarcolemmal KATP may provide a basic protection against ischemia by energy sparing, while both the sarcolemmal KATP and mitochondrial KATP channels are necessary for the ischemia preconditioning. KATP channels also have important functions including homeostasis maintenance and vascular tone regulation under physiological conditions. Further elucidation of the role of KATP in the cardiovascular system will help us to regulate cell metabolism or prevent damage caused by abnormal channel functions. [Copyright &y& Elsevier]