Protection of ischemic postconditioning on cochlear ischemia and reperfusion injury in rats / 中国耳鼻咽喉头颈外科

ABSTRACT

OBJECTIVE To investigate the effect of ischemic postcondioning on cochlea following cochlear ischemia-reperfusion injury in rats. METHODSForty two healthy male SD rats were randomly divided into 3 groups, namely, the sham operation control group, the ischemia reperfusion group and ischemic postcondinging group. There were 14 rats in each group. The content of molondialdehyde(MDA) as well as the activity of catalase(CAT)in cochlea was measured by histochemistry. The ultrastructural changes of stria vascularis capillaries of the cochlea in experimental rats were examined by transmission electron microscopy(TEM). RESULTS In the ischemia reperfusion group, the CAT activities were decreased and MDA concentrations were increased significantly compared with those in the control group. However, in the ischemic postcondinging group, the activities of CAT were increased and MDA concentrations were decreased compared with those in the ischemia reperfusion group. Moreover, lesions were detected in the stria vascularis capillaries in all the three groups. The capillaries of stria vascularis were injured severely in ischemia reperfusion group. In the ischemic postcondinging group, the damage of capillary of stria vascularis were reduced significantly compared with that in ischemia reperfusion group, the structures were near normal, and no obvious destruction was observed. COCLUSION Ischemic postconditioning may markedly reduce the excessive generation of oxygen free radical during the process of ischemia-reperfusion injury and might be a potential strategy for its therapy.