Effects of adenosine postconditioning on serum concentrations of IL-10 and TNF-α following myocardial ischemia-reperfusion in rats

Objective To investigate the effects of adenosine postconditioning (AP) on serum IL-10 and TNF-α concentrations following myocardial ischemia-reperfusion(VR)in rats.Methods Twenty-four SD ratsweighing 180-250 g were randomly divided into 4 groups(n=6 each):group I sham operation (group S);group Ⅱ myocardial I/R;group Ⅲ ischemic postconditioning(group IP)and group Ⅳ AP.Myocardial I/R was induced by 30 rain occlusion of anterior descending branch of left coronary artery followed by 120 min reperfnsion.IP was induced by 3 cycles of 30 s myocardial ischemia followed by 30 s reperfusion at the end of ischemia.In AP group adenosine 1.5 mg/kg was infused at 40μg·kg-1·min-1 before the onset of reperfusion.SP,DP and HR were recorded before ischemia (baseline) at 30 min of ischemia and 30 and 120 min of reperfusion.Arterial blood sarnples were collected at 120 min of repednsion for determination of serum TNF-α and IL-10 concentrations.The animals were then killed.Their hearts were removed for microscopic examination.Myocardial infarct size was measured and myocardial MDA content was determined.Results BP and HR were signilicandy decreased during reperfusion while myocardial infarct size.MDA content and serum concentrations of IL-10 and TNF-α were significantly increased in I/R group compared with group S.Ischemic and adenosine postconditioning significantly attenuated hypotension,reduced infarct size,myocardial MDA content and serum TNF-α concentration and increased serum IL-10 concentration in group AP and IP as compared with I/R group.There was no significant difference in the above changes between group AP and IP. Myocardial injury was ameliorated in group AP and IP as compared with I/R group. Conclusion Adenosine postconditioning can protect myocardium from I/R injury by increasing IL-10 production and inhibiting TNF-a release. Key words: Adenosine; Interleukin-10; Tumor necrosis factor-alpha; Myocardial repedusion injury