Diazoxide Cardioprotection Is Independent of Adenosine Triphosphate-Sensitive Potassium Channel Kir 6.1 Subunit in Response to Stress

Abstract

Background-The sarcolemmal adenosine triphosphate-sensitive potassium channel (sK ATP ), composed primarily of Kir6.2 and SUR2A subunits, has been implicated in cardiac myocyte volume regulation during stress; however, it is not involved in cardioprotection by the K ATP channel opener diazoxide. Paradoxically, the sK ATP channel subunit Kir6.2 is necessary for detrimental myocyte swelling secondary to stress. The Kir6.1 subunit may also contribute to K ATP channels in the heart, and we hypothesized that this subunit may play a role in myocyte volume regulation in response to stress.