Objective To investigate the influence of ischemic reperfusion and ischemic preconditioning on the cardiac structure and function and markers of myocardial injury, especialy on the heine oxygenase-1/carbon monoxide HO...Objective To investigate the influence of ischemic reperfusion and ischemic preconditioning on the cardiac structure and function and markers of myocardial injury, especialy on the heine oxygenase-1/carbon monoxide HO-1/CO reactive system. Methods Mode of langendorff was used in isolated rat hearts with retrograde perfusion. Ischemic reperfusion protocol: perfusion for 60 minutes, stopping perfusion for 30 minutes and reperfusion for 30 minutes. Ischemic preconditioning protocol: perfusion for 30 minutes, stopping perfusion for 5 minutes and reperfusion for 5 minutes and repeating three times, stopping perfusion for 30 minutes and reperfusion for 30 minutes. Control protocol: perfusion 120minutes. HO-1 enzyme activity and HbCO levels in myocardium of each group were measured at reperfusion 30minutes. The HO-1 mRNA and protein expression in rat left ventricular myocardium after reperfusion 30 min were examined by RT-PCR and werstern blotting and immunohistochemistry. Indexes of Cardiac Function were recorded in control group, ischemia and reperfusion group(IR) and ischemic preconditioning group (IPC). Indexes of cardiac injury and cardiac oxidative activity were examined. The changes of myocardial structure were checked up by electron microscopy. Results At reperfusion 30min, the indexes of cardiac function in IPC group were significantly higher than that in IR group (P<0.01), but lower than that in control group(P<0.05) and recovery percentage of cardiac function showed the same changes. The activity of HO-1 and the contents of HbCO in myocardium were increased significantly in IR and IPC(P<0.01), but that of IPC were higher (P<0.01). The expression of HO-1 mRNA and Protein in myocardium were also increased significantly in IR and IPC (P<0.01),but that of IPC were higher (P<0.01). The contents of LDH and total CK and MDA were significantly decreased in IPC Compared to IR (P<0.01) and the activity of SOD were increased remarkably in IPC (P<0.01) and there were differnce betwecn IR and IPC (P<0.01). The localization of HO-1 protein expression in myocardium of rat hearts showed intense staining in the interstitial spaces and perivascular region of blood vessel and moderate staining in the cardiomyocytes and endocardium in IPC and IR, but IPC was more distinct. The myocardial structure injury in IR were the most grievous and the injury were significantly recoveried in IPC. Conclusion The activity of endogenous HO-1/CO reactive system were significantly higher in ischemic reperfusion and preconditioning of isolated rat hearts and might be related with cardiac protection induced by ischemic reperfusion.展开更多
文摘Objective To investigate the influence of ischemic reperfusion and ischemic preconditioning on the cardiac structure and function and markers of myocardial injury, especialy on the heine oxygenase-1/carbon monoxide HO-1/CO reactive system. Methods Mode of langendorff was used in isolated rat hearts with retrograde perfusion. Ischemic reperfusion protocol: perfusion for 60 minutes, stopping perfusion for 30 minutes and reperfusion for 30 minutes. Ischemic preconditioning protocol: perfusion for 30 minutes, stopping perfusion for 5 minutes and reperfusion for 5 minutes and repeating three times, stopping perfusion for 30 minutes and reperfusion for 30 minutes. Control protocol: perfusion 120minutes. HO-1 enzyme activity and HbCO levels in myocardium of each group were measured at reperfusion 30minutes. The HO-1 mRNA and protein expression in rat left ventricular myocardium after reperfusion 30 min were examined by RT-PCR and werstern blotting and immunohistochemistry. Indexes of Cardiac Function were recorded in control group, ischemia and reperfusion group(IR) and ischemic preconditioning group (IPC). Indexes of cardiac injury and cardiac oxidative activity were examined. The changes of myocardial structure were checked up by electron microscopy. Results At reperfusion 30min, the indexes of cardiac function in IPC group were significantly higher than that in IR group (P<0.01), but lower than that in control group(P<0.05) and recovery percentage of cardiac function showed the same changes. The activity of HO-1 and the contents of HbCO in myocardium were increased significantly in IR and IPC(P<0.01), but that of IPC were higher (P<0.01). The expression of HO-1 mRNA and Protein in myocardium were also increased significantly in IR and IPC (P<0.01),but that of IPC were higher (P<0.01). The contents of LDH and total CK and MDA were significantly decreased in IPC Compared to IR (P<0.01) and the activity of SOD were increased remarkably in IPC (P<0.01) and there were differnce betwecn IR and IPC (P<0.01). The localization of HO-1 protein expression in myocardium of rat hearts showed intense staining in the interstitial spaces and perivascular region of blood vessel and moderate staining in the cardiomyocytes and endocardium in IPC and IR, but IPC was more distinct. The myocardial structure injury in IR were the most grievous and the injury were significantly recoveried in IPC. Conclusion The activity of endogenous HO-1/CO reactive system were significantly higher in ischemic reperfusion and preconditioning of isolated rat hearts and might be related with cardiac protection induced by ischemic reperfusion.
