Ischemic postconditioning reduces myocardial damage in rats suffering from limb ischemia-reperfusion
AIM; To investigate the protective effect of limb ischemic postconditioning on the myocardial dam-age in the rats suffering from limb ischemia -reperfusion (LIR). METHODS: Wistar rats were randomly divided into control group ( C group) , ischemia - reperfusion group (IR group) and ischemic post - conditioning group (IR + IPostC group). For conducting ischemic postconditioning, the rats in IR + IPostC group underwent 5 min of ischemia and 5 min of reperfusion on their hind limbs repeatedly after 4 h of ischemia, and then, 4 h of reperfusion was applied. The activity of superoxide dismutase (SOD) , xanthine oxidase (XOD) and myeloperoxidase (MPO) was measured. The levels of malon-aldehyde ( MDA) in plasma and myocardial tissues, the levels of creatine kinase ( CK) , creatine kinase MB ( CK - MB) , aspartate aminotransferase (AST) , lactate dehydrogenase (LDH) , a - hydroxybutyrate dehydrogenase (a - HBDH) and myocardial troponin I (cTnl) were also detected. The changes of ultrastructure in the myocardium were observed under e-lectron microscope. RESULTS: Compared with C group,the levels of CK - MB, AST, LDH,α - HBDH and cTnl were all increased in IR and IR + IPostC groups. The levels of MDA and XOD also increased ( P < 0. 05 ) , but the activity of SOD decreased (P <0. 05) . However, compared with group IR, the levels of CK - MB, AST, LDH, a - HBDH and cTnl de-creased ( P < 0. 05 ) in IR + IPostC group. The levels of MDA and XOD also decreased ( P < 0. 05 ) , but the activity of SOD increased (P<0. 05). Under electron microscope, the cardiac myofibrils arranged neatly, light and dark bands were clear, the mitochondrial cristae arranged closely and neatly, and the mitochondrial matrix densification was observed in Cgroup. However, the cardiac fiber arrangement was disordered or disappeared, stromal edema was obvious, most or all mi-tochondrial cristae and membrane became fusion or disappeared, mitochondrial vacuolization and decrease in glycogen were obvious in IR group. In IR + IPostC group, the pathological changes mentioned above were attenuated somewhat than those in IR group. CONCLUSION: Ischemic postconditioning protects rat myocardium under limb ischemia - reperfusion.
国家科技期刊平台
NSTL
万方数据
维普
