Expression Study Of CDC42 In Brain Tissue Of Rats With Ischemia-reperfusion Injury

Objective: To observe the expression of cell division cycle42 in brain tissue after cerebral ischemia reperfusion in rats.At the same time,to investigate the effect of ML141,specific inhibitor of CDC42,on Zea-Longa score and brain infarct volume of ischemia reperfusion rats.Methods: Male Sprague-Dawley rats were randomly divided into nine groups,including ischemia reperfusion model group(5 groups: 6 h,24 h,72 h,1 w,2 w),normal group,sham group,ML141 group and DMSO group.This experiment used middle cerebral artery occlusion to establish cerebral ischemia reperfusion model.The degree of neurological deficit was evaluated by modified Zea-Longa score.The expression of CDC42 in brain tissue was detected by western bolt and immunohistochemistry.HE staining was used to observation of pathological changes after cerebral ischemia reperfusion injury.The infarct volume of rat brain tissue was measured by TTC staining.Results:1.The results of Zea-Longa score showed that except the normal group and sham group,each group had different degrees of neurological impairment,and the differences were statistically significant compared with the normal group(P < 0.05).2.The results of western blot showed that CDC42 expressed in the brain tissue of rats in each group.The basic expression of CDC42 was found in the normal group and sham group.There was no significant difference between the two groups.CDC42 of 6h group and 24 h group expressed lower than normal group.The differences compared with normal group were statistically significant(P < 0.05).CDC42 of 72 h group and 1w group were close to normal level,and there was no significant difference compared with the normal group.But in 2w group,CDC42 decreased again.The difference was statistically significant(P < 0.05)compared with the normal group.3 The results of HE staining showed the arrangement and structure of brain tissue cells were clear and complete in the normal group.In 1w group,the arrangement of brain tissue cells was irregular,the structure was disordered,and the nucleus was pyknosis.4.The results of immunohistochemistry showed CDC42 expressed in the cytoplasm of cells in DG zone of hippocampus of rats.5.The results of Zea-Longa score after ML141 intervention showed that the Zea-Longa score of ML141 group was lower than 1w.The difference was statistically significant(P < 0.05).There was no significant difference between the score of DMSO group and that of 1 w group.6.The results of TTC staining showed that there was no infarct focus in normal group,and there were different sizes of infarcted volume in 1w group,ML141 group and DMSO group.The infarct volume of ML141 group decreased significantly compared with 1w group(P < 0.05).There was no significant difference between DMSO group and 1w group.7.The results of western blot after ML141 intervention showed that CDC42 of ML141 group expressed lower than normal group and 1w group(P < 0.05).There was no significant difference between DMSO group and 1w group.Conclusion: The expression of CDC42 in the brain tissue of cerebral ischemic rats was dynamic after ischemia-reperfusion.After the application of ML141,the specific inhibitor of CDC42,the degree of neurological deficit and the infarct volume decreased.It suggested that CDC42 may be involved in the mechanism of cerebral ischemia-reperfusion injury.