Dynamic Changes Of Ca Fe Cu Zn Mg C-Fos NF-κB And Protective Effects Of MgSO₄ Due To Brain Injury In Irradiated Rats

Part 1:Dynamic changes of Ca Fe Cu Zn Mg and protective effects of MgSO₄due to brain injury in irradiated ratsPurpose:Establishing the RBI（radiation-induced brain injury）rats model and investigating the dynamic changes of brain water content,micro-vascular injury and Ca,Fe,Cu,Zn,Mg content of hippocampal tissue in the injured brain of irradiated rats,to explore the role of these elements in the pathogenesis of RBI.Method:The rats were divided into the control group,the protective group（by intraperitoneal injection of 400 mg/kg body weight 10%MgSO₄ solution+a single whole brain 20 Gy electron beam irradiation）and the irradiated group（by intraperitoneal injection of 400 mg/kg body weight normal saline+a single whole brain 20 Gy electron beam irradiation）,18 in each group,and three in each time point.whole brain of the protection group and the irradiated group were irradiated by electron beams（5 Me V）once,namely radiation-induced brain injury（RBI）,to detect brain water content（BWC）with a dry-wet weight method,to detect the level of micro-vascular injury with HE staining brain tissue slice,and using inductively coupled plasma emission spectroscopy to quantitative analysis Ca,Fe,Cu,Zn,Mg contents of hippocampus at different time point after radiation.Results:（1）BWC in 7,14 and 30 d of the irradiated group was higher than that in the blank group（t=3.21,-2.11,2.82,P<0.05）,and in 7,14 and 30 d of the protective group was less than that in the irradiated group（t=2.84,4.33,1.90,P<0.05）;（2）Forming different levels of micro-vascular thrombosis in the RBI,and the protective group was less than that in the irradiated group;（3）Ca content in different time and Fe content in 1,3,7 d of the irradiated group was higher than that in the blank group（t=11.41,6.81,14.03,17.17,6.89,9.12 and5.43,5.66,3.60,P<0.05）,and Ca content in different time of the protective group was less than that in the irradiated group,（t=5.35,5.28,11.02,14.26,5.68,9.10,P<0.05）;（4）Cu content in 1,7,14,60 d and Zn content in 1,7,14,30,60 d of the irradiated group was less than that in the blank group（t=4.24,3.76,4.76,3.86and5.25,4.78,26.53,6.67,11.37,P<0.05）,and Cu content in different time of the protective group was less than that in the irradiated group（t=4.23,3.57,4.01,4.73,3.78,3.44,P<0.05）,Zn content in 14 d of the protective group was higher than that in the irradiated group（t=6.21,P<0.05）;（5）Mg content in 7 d of the irradiated group was less than that in the blank group（t=5.85,P<0.05）.Conclusion:Ca,Fe,Cu and Zn content was imbalance in the RBI,supplementing MgSO₄could correct the imbalance of Ca,Fe,Cu and Zn content,and alleviate radiation-induced brain injury.Part 2:Expression changes of c-Fos NF-κB and protective effects of MgSO₄ due to brain injury in irradiated ratsPurpose:Establishing the RBI（radiation-induced brain injury）rats model and investigating the dynamic changes of c-Fos and NF-κB genes,to explore the role of these genes in the pathogenesis of RBI.Method:The rats were divided into the control group,the protective group（by intraperitoneal injection of 400 mg/kg body weight 10%MgSO₄solution+a single whole brain 20 Gy electron beam irradiation）and the irradiated group（by intraperitoneal injection of400 mg/kg body weight normal saline+a single whole brain 20 Gy electron beam irradiation）,18 in each group,and three in each time point.whole brain of the protection group and the irradiated group were irradiated by electron beams（5 Me V）once,namely radiation-induced brain injury（RBI）,Real-time quantitative reverse transcriptase-PCR was used to measure the level of NF-κB/c-Fos m RNA in the hippocampus tissue.The expression of NF-κB/c-Fos protein in the hippocampus tissue was detected with Western blot.Results:The expression of c-Fos and NF-κB were increasing in RBI models after irradiated,and the protective group were less than the irradiated group.It is that c-Fos and NF-κB could be used as evaluation index of RBI.