CXCR4 and myocardial infarction: To examine the roles of SDF-1α/CXCR-4 in Ang-1-induced CD133+ cell recruitment into db/db mouse hearts, we examined the number of CXCR-4+ cells and SDF-1α/CXCR-4 protein expression in the border zone of infarcted myocardium after 24 hours of MI.