HIF1A and myocardial ischemia: To assess the functional consequences of global-induced deletion of Hif1a in myocardial ischemia and reperfusion injury, we exposed Hif1aloxP/loxP Ubiquitin Cre+ mice to in situ myocardial ischemia and reperfusion after treatment and recovery with tamoxifen (Figure 1A) and evaluated myocardial injury by infarct sizes and serum troponin levels.