The Expression Of Caspase-9 After Focal Cerebral Ischemia-reperfusion Injury In Rats And Further Intervention Of Minocyeline

Objectives:Establish the rat focal cerebral ischemia reperfusion model to observe Caspase-9 expression in brain and the influence of apoptosis and Caspase-9 express with Minocyeline for expounding the antiapoptotic mechanism and providing laboratory data to the clinical application.Methods:This research makes use of the focal cerebral ischemia reperfusion model induced by middle cerebral artery occlusion(MCAO) through suture method for 120 minutes followed by reperfusion for 72 hours in rats.36 healthy male SD rats(250±10)g were randomly divided into sham group(n=12), ischemia reperfusion group(I/R)(n=16), Minocycline group(n=8). To judge the model bases on Zealonga's scoring and TTC staining results. HE staining of brain histopathological changes and further intervention of Minocyeline on the expression of Caspase-9 and cell apoptosis in the focal cerebral ischemia reperfusion were used to be observed.Results:1,The rats are normal in sham group, but development typical symptoms of neurological impairment in I/R group.2,TTC staining showed the cerebral tissue is red in sham group, cortex of ipsilateral prefrontal parietal temporal lobe and external corpora striatum is white in I/R group.3,HE staining showed the morphology of neurons of sham group was normal.In I/R group, the neurons in ischemia penumbra area(cortex of ipsilateral prefrontal lobe and internal corpora striatum)and hippocampus region were very little in size and amount array disorderly and loose.There existed a lot of apoptotic neurons, showed karyopyknosis, chromatin concentration, nuclear fragmentation, et al.In Minocycline group, the number of normal neurons in ischemia penumbra and hippocampus CA1 region increased, The normal neurons and apoptotic neurons are staggered. 4,Apoptotic cell showed nuclear in the TUNEL assay.There were few positive cells in sham group, while in I/R group, positive cell increased gradually, appeared in both ischemic central and penumbra area.In Minocycline group, there were less positive cell than ischemia and reperfusion group(p<0.05).5,There was trace expression of Caspase-9 protein in Sham group.The expression of Caspase-9 is apparent in I/R group(p<0.05).Their spatial distributions were coincidence with the result of TUENL assay.The expression of Caspase-9 became apparent in Minocycline group than that in sham group, but compared with ischemia and reperfusion group, the expression of Caspase-9 in Minocycline group became significantly weaker(P<0.05).Conclusions:1,The MCAO model can make brain Caspase-9 expression increased.2,Both of the expression of Caspase-9 protein in I/R group and Minocycline group increased, the expression in I/R group was more obvious than in Minocycline group.3,Minocycline tends to reduce the brain organization pathological changes after ischemia reperfusion and has the nerve protection.4,Minocycline obviously inhibited focal cerebral ischemia induced apoptosis in ischemic penumbra area and hippocampus CA1 region relieve neuronal injury.5,Minocycline can decrease neuronal apoptosis and inhibit the expression Caspase-9 protein in the cerebral ischemia reperfusion.