Effects Of Cardic Ischemic Postconditioning And Intervention Of L.name On Serum Cytokines In Rats

Background: Brief periods of ischemia and reperfusion performed just at the time of reperfusion could limit the damage induced by subsequent ischaemia/reperfusion injury and this phenomenon was called ischemic postconditioning.Objectives: To determine whether ischemic postconditioning could affect the level of inflammatory cytokines and the intervention of Nitric Oxide synthase inhibitor L.NAME in this phenomenon.Methods: Male SD rats(n=50)were randomly divided into five groups, including sham group, ischaemia/reperfusion (I/R) group , postconditiong(IPost)group, L.NAME-treated before postconditiong (L.NAME+IPost) group and L.NAME-treated before ischaemia/reperfusion (L.NAME+I/R) group . In this process,blood was drawn to assay serum IL-6 and IL-10 levels at 15 min, half an hour, one hour and two hour after reperfusion with ELISA method. Rats were killed for measuring myocardial infarct size with 2,3,5 triphenyltetrazolium chloride (TTC) staining.Results: The proportion of infarct size in latter four groups was 17.08%, 6.34%, 16.93% and 17.12%, respectively. IPost reduced the infarct size (P<0.05),and this protection disappeared when L.NAME was given before ischaemia/reperfusion. IPost could reduce the serum level of IL-6 and increase the level of IL-10 in the Ipost group compared with those in the I/R group (P<0.05), but such changes had not shown when L.NAME was given before ischaemia/reperfusion. There was no significant difference of IL-10 and IL-6 levels between the I/R group and L.NAME+I/R group (P>0.05).Conclusions: The present study demonstrates that Ischemic Postconditioning can reduce myacardia infact size induced by ischaemia/reperfusion injury. The protective effect of Ischemic Postconditioning may be involved in decrease of proinflammatory cytokines level and increase of anti-inflammatory cytokines which modulated by enhancement of endothelial nitric oxide synthase activity.