Glutamate Intake And Expression Of ICAM-1,NF-?B P65 By Astrocytes In Mice Hippocampus After Ischemia

Objectives To investigate the infarct volume of brain tissue and neuronal changes in hippocampus after MCAO in mice;To investigate the change of astrocytes in hippocampus after MCAO in mice;To investigate the expression of EAAT-2,ICAM-1 and NF-?B P65 by astrocytes in hippocampus after MCAO in mice;To further appraise the mechanism of EAAT-2 and Inflammatory factors expressed by astrocytes in hippocampus after MCAO in mice.Methods 1 Ischemia model were made by new Suture method in right common carotid artery among male KM mice,the mice were randomly divided into three groups: ischemia group,sham Operation group and normal group.Ischemia groups consisted by 1h,3h,6h,12 h,24h,48 h after MCAO.Sham Operation groups consisted by 1h,3h,6h,12 h,24h,48 h after sham operation.2 Investigate the infarct volume of brain tissue in normal groups and ischemia groups by TTC staining.3 The remaining mice were sacrificed before cardiac perfusion of paraformaldehyde,the hippocampus was taken from the brain and then make a paraffin section.4 We use the HE staining method to observe the morphology of neurons in hippocampus of normal group and ischemia groups.5 We investigate the morphology of GFAP in hippocampus after immunochemistry with normal group,sham operation group and ischemia group.6.We compared the experssion of EAAT-2,ICAM-1 and NF-?B P65 by astrocytes in hippocampus after Immunofluorescence with each groups.7 All experimental data were compiled with Microsoft Excel 2016.Statistical analyses were performed with SPSS software(version 22.0).Measurement data were expressed as mean ± standard deviation(SD).Intragroup differences were compared with one-way analysis of variance.Values of P<0.05 were considered to be statistically significant.Results 1 Different degrees of neurological deficts appeared after operation in ischemia group,neurological deficts did not appear in Sham operation group.2 The ischemic area were expended in 48 hours after ischemia,the hippocampus infarcted after 6h of MCAO.3 Neurons in normal group were not changed,but in right hippocampus of ischemia group were injured after ischemia,a large number of neurons appeared edema after 3h MCAO,Irreversible injury appeared after 6h of MCAO,and neurons in left hippocamous were injured after 12 h of MCAO.4 The result of GFAP by immunohistochemistry labeling: normal group and sham operation group found a small amount of positive GFAP-labeled cells(P>0.05). Ischemia group: GFAP-labeled cells increased after ischemia(p<0.05),reaching a peak value at 6h.Comparing normal group and sham operation group,the differences were significant(p<0.05).5 The result of GFAP and EAAT-2 immunofluorescent labeling: EAAT-2 positive cells increased after ischemia,and almost co-staind with GFAP positive cells,the astrocyte marker,in right hippocampus.The co-staind cells of GFAP and EAAT-2 gradually increased in 24 hours after MCAO(P<0.05).6 The result of GFAP and ICAM-1 immunofluorescent labeling: ICAM-1 positive cells increased after ischemia,but seldom co-staind with GFAP positive cells in hippocampus of each groups,GFAP and ICAM-1 co-staind cells gradually increased after 12 h of MCAO(P<0.05).7 The result of GFAP and NF-?B P65 immunofluorescent labeling: NF-?B P65 positive cells increased after ischemia,but seldom co-staind with GFAP positive cells in hippocampus of each groups,GFAP and NF-?B P65 co-staind cells gradually increased after MCAO(P<0.05).Conclusions Neurons in bilateral hippocamous were injured after ischemia in mice,the ischemia side was more seriously.astrocytes have a rapid responds and proliferation at the same time.The expression of EAAT-2 by activated astrocytes was enhanced after ischemia,meanwhile,the experession of ICAM-1 and NF-?B P65 were also enhanced.