伽玛射线对大鼠海马组织的放射生物学作用  

Radiobiological response of rat hippocampus irradiated with gamma knife

作　　者：韩春雷[1] 孟凡刚[1] 潘剑[1] 刘阿力[1] 张凯[2] 张建国[2] 

机构地区：[1]首都医科大学北京市神经外科研究所,100050 [2]首都医科大学附属北京天坛医院神经外科

出　　处：《中华实验外科杂志》2013年第9期1841-1843,共3页Chinese Journal of Experimental Surgery

基　　金：北京市卫生系统高层次卫生技术人才培养计划资助项目（2011-3-032）;中国博士后科学基金资助项目（20060400094）;北京市优秀人才培养资助项目（2009D003034000002）

摘　　要：目的 通过磁共振成像（MRI）、超微结构评估不同剂量伽玛射线对大鼠海马组织的影响,并分析照射前后大鼠基因表达谱的变化.方法 分别用照射剂量为20、40、60和l00 Gy的伽玛射线对正常大鼠海马进行照射,于照射后3、5和7个月进行MRI检查,于照射后3个月进行电镜检查,同时用基因芯片技术检测照射剂量为25 Gy时基因表达谱的变化,并对差异基因进行功能分类.结果 照射剂量为20 Gy时,大鼠MRI和电镜检查未见明显变化,随着照射剂量的增加和时间的延长,逐渐出现放射性损伤.MRI表现为混杂信号,电镜显示神经元固缩、内皮细胞破坏等变化.差异基因涉及生物学进程、分子组成等功能.结论 伽玛射线对大鼠海马组织的放射生物学作用与照射剂量有关.基因芯片技术可检测伽玛刀照射前后基因表达谱变化,并对差异基因进行功能分类.Objective To investigate the effect of Leksell gamma knife irradiation on normal rat hippocampus through magnetic resonance imaging （MRI） and ultra-structure and analyze the gene expression profile of the rat hippocampus before and after the irradiation of the Leksell gamma knife.Methods The normal rats were irradiated with doses of 20,40,60 and 100 Gy,and 4-mm isocenters were used to cover the right hippocampus.MRI was performed at 3rd,5th and 7th month after radiosurgery with gamma knife.Rat was killed and the brain was removed to receive ultra-structural examination at 3rd month after irradiation under electron microscope.Meanwhile,we used gene chip to investigate the expression profile of genes and their function in the rats 3 months after irradiation with 25 Gy and 8-nm isocenters.Results After irradiation with 20 Gy,there were no obvious changes on MRI and ultra-structural examinations of the rat hippocampus.The damages of rat brain were aggravated with the increase of irradiation dose and the extension of duration.Mixed signals occurred in MRI,and electron microscopy showed neuronal pyknosis,endothelial cell damage,etc.The genes differentially expressed were categorized into different functions incIuding molecular function,biological process,cellular component,etc.Conclusion The effect of gamma knife on brain tissue appeared gradually with the extension of time and the increase of irradiation dose.The microarray analysis can screen the genes differentially expressed before and after irradiation,and classify the differentially expressed genes functionally.

关 键 词：伽玛刀 海马 基因表达 微阵列分析 

分 类 号：R817[医药卫生—影像医学与核医学]