Our data demonstrates that 1) a regional heterogeneity exists between GLUT4 and 8 expression in atria vs. ventricle; 2) both GLUT-4 and -8 are insulin-sensitive in the healthy atria; 3) diabetes impaired GLUT-4 and -8 trafficking to the atrial cell surface; and 4) insulin stimulation rescued GLUT translocation to the atrial cell surface during type 1 diabetes. Here, SLC2A4 is linked to diabetes mellitus.