Experimental acute myocardial infarction in rats: HIF-1α, caspase-3, erythropoietin and erythropoietin receptor expression and the cardioprotective effects of two different erythropoietin doses.

Abstract The cardioprotective effects of two different doses of erythropoietin administration were analyzed in rats with experimental myocardial infarction. None, saline, standard-dose (5000 U kg −1 ) and high-dose (10,000 U kg −1 ) of human recombinant erythropoietin alpha were administered intraperitoneally in Wistar rats with myocardial infarction induced by coronary artery ligation. Infarct sizes measured after triphenyltetrazolium chloride staining, levels of biochemical markers, histopathology examined by light and electron microscopy, and immunohistochemical expressions of erythropoietin, erythropoietin receptor, hypoxia inducible factor-1α and caspase-3, were analyzed. Lower scores of infarction and hemorrhage, lower number of macrophages and higher score of vascularization surrounding the infarct area were observed in the erythropoietin administered groups ( p p