More importantly, our in vivo study revealed that intramyocardial injection of GLUT4 siRNA significantly decreased GLUT4 expression and thus blocked the cardioprotection of IPC as evidenced by increased myocardial infarct size in IPC-treated I/R hearts, confirming the critical role of glucose uptake in the beneficial effects of IPC. The gene discussed is SLC2A4; the disease is myocardial infarction.