Research On The Time Window To Activate Autophagy After Limb Ischemia Postconditioning In Cerebral Ischemia Reperfusion

Objective: To investigate the role of autophagy in cerebral ischemia reperfusion injury after limb ischemic postconditioning,and study the time window of autophagy activation.Methods: The focal cerebral ischemia reperfusion model in rats was established by embolism line methods.Rats were randomly divided into four groups,sham-operated group(sham group),ischemia reperfusion group(I/R group),limb ischemia postconditioning group(LPost C group),and inhibitor of autophagy group(3-MA group),the rats in ischemic postconditioning group were subdivided into 0 min subgroup,10 min subgroup and 30 min subgroup.After 24 h reperfusion,Groups of neurologic tests and analysis were recorded,to measure the volume of cerebral infarction volume in rats,HE staining was used to observe the pathological changes and the number of changes,the samples of each group underwent immunohistochemistry staining to observe the expressions of autophagy-associated protein LC3-II.Results:(1)Compared with ischemia reperfusion group,The score of neurological deficits in LPostCgroup was significantly decreased,Compared with LPost C group,3-MA group ameliorating the neurological function(all P<0.05);(2)Compared with ischemia reperfusion group,the infarct volume of LpostC group was significantly decreased,The infarct volume of 3-MA group was higher than that of group LPost C(all P<0.05);(3)Compared with I/R group,pathomorphology change in LpostC group was significantly reduced,Compared with the LpostC group,3-MA group pathological changes aggravated;(4)Compared with I/R group,the expression of LC3-II was significantly increased in group LPostC,The positive cells in 3-MA group were significantly lower than that in the LPostC group;Compared with the 30 min subgroup,the expression of LC3-II in the 0 min subgroup and 10 min subgroup was increased(all P<0.05).Conclusion: Limb ischemic treatment increased the expression of LC3-II and the activity of autophagy was activated,which can protect cerebral ischemia reperfusion injury.Moreover,reperfusion immediately after limb ischemia treatment intervention activated autophagy was most significant.