Effect of diabetes mellitus factor on attenuation of myocardial ischemia-reperfusion injury by sufentanil postconditioning in rats

Objective To investigate effect of diabetes mellitus factor on attenuation of myocardial ischemia-reperfusion injury by sufentanil postconditioning in rats.Methods Diabetes mellitus was established by intraperitoneal streptozotocin 50 mg/kg and was confirmed by blood glucose ≥ 16.7 mmol/L.Thirty healthy adult male SD rats,weighing 250-300 g which diabetes mellitus model was successfully established were randomly divided into 3 groups ( n =10 each):diabetic mellitus sham operation group (group DM-S),diabetic mellitus ischemia-reperfusion group (group DM-IR) and diabetic meltitus sufentanil postconditioning group (group DM-SP).Another 30nondiabetic mellitus rats were also randomly divided into 3 group ( n =10 each):nondiabetic mellitus sham operation group (group NDM-S),nondiabetic mellitus ischemia-reperfusion group (group NDM-IR) and nondiabetic mellitus sufentanil postconditioning group (group NDM-SP).Myocardial ischemia-reperfusion was induced by 30 min occlusion of left anterior descending branch of coronary artery followed by reperfusion.Sufentanil postconditioning was induced by iv injection of sufentanil 1.0 μg/kg at 5 min before reperfusion.MAP,SBP,HR and RPP (HR × SBP) were recorded before ischemia,30 min of ischemia and 120 min of reperfusion.Arterial blood samples were collected at 120 min of reperfusion for measurement of plasma cardiac troponin 1 (cTnI) concentration.The animals were then sacrificed for determination of total areas of right and left ventricles ( LV + RV),infarct area (IS),area at risk (AAR) and IS/AAR.Results MAP and RPP were significantly lower,while plasma cTnI concentration was higher during myocardial ischemia reperfusion in diabetic and nondiabetic rats.Sufentanil postconditioning significantly decreased IS,IS/AAR and plasma cTnI concentration in nondiabetic rats during myocardial ischemia reperfusion but had no effect on IS,IS/AAR and plasma cTnI concentration in diabetic rats.The IS,IS/AAR and plasma cTnI concentration were significantly higher in DM-SP group than in NDM-SP gnoup ( P ＜ 0.05).Conclusion Diabetes mellitus factor can negate sufentanil postconditioning induced protection against myocardial ischemia-reperfusion injury in rats. Key words: Diabetes mellitus;  Sufentanil;  Myocardial reperfusion injury;  Postconditioning