The Effects Of Dexamethasone On Nerve Cell Morphology Of Hippocampal CA1 Area Of Mice After Cerebral Ischemia And Reperfusion

Objective:For further verification of the feasibility of experimental animal model for cerebral ischemia-reperfusion injury,the effect of dexamethasone intervention after reperfusion on cerebral ischemia-reperfusion injury was preliminarily studied,along with the optimal time for dexamethasone intervention.Methods:54 healthy Kunming mice,half male and female,mass 20±2 grams.According to random number table,they are divided into 9 groups,6 mice in each group.Respectively,for sham-operated group(I),only dissociate bilateral carotid artery,for 4 saline control groups(N1, N2,N3,N4),silk ligate bilateral common carotid artery,and 1 hour later release them,the groups are given considerable amount of grant saline via the tail vein after 0h,0.5h,1h,1.5h of reperfusion respectively,and for dexamethasone 4 intervention groups(D1,D2,D3,D4),silk ligate bilateral common carotid artery,and release them 1h later,the groups are given dexamethasone in 10mg/kg via the tail vein after 0h,0.5h,1h,1.5h of reperfusion respectively. The brains of above 9 groups are taken by breaking after 24h of reperfusion.Use the neutral formaldehyde solution to fix them for 24h,then take the brain tissue between the optic chiasm and the back of the optic mamillary.Next,routine dehydration,Baptist wax,transparent,and embedding.Slice thickness is 5um,taken from chiasm 2 planar chips after the optic,stained by HE.Under the light microscope of the micrometer scale microscope(×10),count the complete nuclear cone cells within 2mm from the beginning of hippocampal CA1 area with Blind Method.Experimental data use mean±standard deviation((?)±s).The saline group compared groups uses one-way ANOVA,sham-operated group compare with the saline group by two-sample t test,dexamethasone group 4 compare with the saline group 4 use analysis factorial design.Results:Comparison within saline groups,P＞0.05,no statistical significance,saline group compared with the sham-operated group,two-sample t test results indicate:homogeneity of variance with a significant difference,P＜0.001,comparing saline group with dexamethasone group,analysis of variance test results showed that the main effect of time was significant,P＜0.001,with the time,the number of normal cells gradually reduce.Packet effect has a statistically significance,P＜0.001,significant difference lie between dexamethasone group and saline group.Time interacts with the sub-groups,P＜0.001,and the differences between dexamethasone group and saline group come down over time.Conclusion:High-dose dexamethasone can improve brain cell damage after the cerebral ischemia-reperfusion early,medication and the sooner the better.