AimTo investigate the effects of different dosage of atorvastatin postconditioning and its mechanisms on myocardial ischemia-reperfusion injury in GK rat.MethodsSeventy GK rats were randomly divided into seven groups (n=10 each)： sham group, ischemia-reperfusion injury (I/R) group, different dosage of atorvastatin (0.1, 0.5, 1 and 2 mg/kg) postconditioning group, atorvastatin＋LY294002.Myocardial infarct size (IS), ultrastructural change and myocardial expression of phosphorylated Akt/totalAkt were determined.ResultsMyocardial infarct size and ultrastructural damages were all reduced, myocardial Akt phosphorylation was significantly increased, and Akt was significantly activated in atorvastatin postconditioning group compared with I/R group.The effects were significant at 1 mg/kg and 2 mg/kg atorvastatin postconditioning group, and were significantly attenuated by PI3K inhibitor LY294002.ConclusionAtorvastatin postconditioning could dose-dependently alleviate myocardial ischemia-reperfusion injury in this type 2 diabetic model, which may probably be associated with the increase of the activating PI3K/Akt signaling pathway in the myocardium.