Myocardial infarction in diabetic rats: role of hyperglycaemia on infarct size and early expression of hypoxia-inducible factor 1

Abstract

Aims/hypothesis. This study aimed to evaluate the effects of hyperglycaemia on the evolution of myocardial infarction and the expression of the transcriptional factor for angiogenesis hypoxia-inducible factor 1α (HIF-1α) in the rat. Methods. We studied the effects of streptozotocin induced diabetes on infarct size and HIF-1 α gene expression. These parameters were also evaluated in isolated hearts of non-diabetic rat, in condition of high glucose concentration. Results. In streptozotocin (STZ)-diabetic rats (in vivo study), myocardial infarct size was greater (pppConclusion/interpretation. Both hyperglycaemia and high glucose concentrations increased basal HIF-1α and Rac1 expression, suggesting a state of pseudohypoxia. These findings show that myocardial infarct size in the rat is increased in hyperglycaemic conditions and is associated with a reduced expression of the HIF-1α gene. These changes are reversed, totally or partially, by normoglycaemia or glutathione suggesting a role for reactive oxygen species generation brought about by hyperglycaemia.