SLC2A1 and ischemia: In contrast to facilitated energy-independent GLUT transport, which may become inefficient under conditions of a low extracellular glucose concentration, SGLTs, as active transporters, work against the glucose concentration gradient by coupling glucose transport to the downhill Na+ electrochemical gradient via Na+/K+ATPase and thus are essential for cardiomyocyte survival in environments with a low glucose concentration, such as that associated with ischemia [11,12,37].