Study on protective mechanism of non-wounded ischemic preconditioning on rat ischemia/reperfusion myocardium

AIM:To investigate probable protective mechanism of non-wounded legs ischemic preconditioning on ischemia/reperfusion(I/R) myocardium. METHODS: 36 male SD rats, weighting (250±30) g,were divided into 4 groups.They are normal control(NC);I/R; classical ischemic preconditioning(C-IPC)and non-wounded legs ischemic preconditioning(N-WIPC). NO in plasm,expression of myocardial HSP 70 mRNA, the activities of 5’-NT and CAT of myocardium were observed in all groups. RESULTS:The level of NO in plasm significantly enhanced in groups C-IPC and N-WIPC compared with that in groups I/R and NC ( P <0.01),expression of myocardial HSP 70 mRNA was greatly increased in both C-IPC and N-WIPC groups, the activities of 5’-NT, CAT of myocardium were also raised in groups C-IPC and N-WIPC ( P< 0.05 vs I/R),but there was no difference between C-IPC and N-WIPC( P >0.05). CONCLUSION:The possible protective mechanism involved in N-WIPC is similar to that in C-IPC, which is due to increase of endogenous myocardial protective substances.