SUR2A is an ATP-binding protein known to serve as a regulatory subunit of metabolic-sensing, cardio protective sarcolemmal ATIP-sensitive K+ (K-ATP) channels. It has been recently found that a moderate increase in expression of SUR2A protects the heart against different types of metabolic stresses, including ischaemia/reperfusion and hypoxia. Although the sarcolemmal K-ATP channel is a multiprotein complex composed of many proteins in vivo, it seems that an increase in SUR2A levels is sufficient to increase the number of sarcolemmal K-ATP channels. This effect of SUR2A could be due to SUR2A being the rate-limiting factor in generating fully composed sarcolemmal K-ATP channels. An increased number of sarcolemmal K-ATP channels seems to protect the heart by regulating action membrane potential, inhibiting Ca2+ influx and preventing Ca2+ overload, although an additional yet to be recognised mechanism independent of K-ATP channels activity cannot be excluded.
- SENSITIVE POTASSIUM CHANNELS
- SARCOLEMMAL K-ATP
- GLYCERALDEHYDE-3-PHOSPHATE DEHYDROGENASE
- ISCHEMIA/REPERFUSION INJURY
- H9C2 CELLS