全脑辐照后大鼠脑组织中髓鞘的变化特征  

Changes of myelin in the rat brain after whole-brain irradiation

作　　者：石志革[1] 包仕尧[1] 田野[1] 

机构地区：[1]苏州大学附属第二医院,苏州215004

出　　处：《辐射研究与辐射工艺学报》2007年第5期289-293,共5页Journal of Radiation Research and Radiation Processing

基　　金：江苏省卫生厅重大科研课题项目(K200406);苏州大学医学发展基金项目(EE123504);江苏省"六大人才高峰"第三批项目资助

摘　　要：为了深入研究电离辐射后大脑组织脱髓鞘病变的发病过程,对受2、10和30Gy全脑的Sprague-Dawley大鼠,在照射后1周以及1、3和6个月时,采用酶联免疫吸附法测量脑组织中髓鞘碱性蛋白(Myelin basic protein,MBP)含量、用Luxol fast blue染色法和电镜观察并分析髓鞘的病理学改变。结果表明,2、10和30Gy照射后1周与1个月的各组大鼠,其端脑组织中MBP的含量与对照组相比均无明显差别,但10Gy和30Gy照射后3个月和6个月中MBP则有明显降低;髓鞘染色显示30Gy照射后6个月大鼠在胼胝体区有较典型的脱髓鞘病变存在,10-30Gy照射后1-6个月各组在超微结构上也有不同程度的髓鞘异常;病理学变化的严重程度与剂量、观察时间有明显的相关性。由此看来,10-30Gy照射后3-6个月的大鼠脑组织中从分子、组织形态到超微结构等方面可出现一系列的髓鞘异常改变。The whole brain of SD rats was irradiated by the single dose of 2, 10, or 30Gy. The enzyme-linked immunosorbent assay was used for the content measurement of myelin basic protein （MBP） in telencephalon tissue at 1 week, 1 month, 3 months and 6 months after irradiation. Both the Luxol fast blue staining with image analysis and the electron microscope were used to investigate the histomorphologic and ultrastructural characteristics of demyelination. The MBP content of telencephalon tissue in control rats were 78-82μg/mL, there were no difference in all the 2Gy irradiated, 1 week and 1 month after 10 to 30Gy irradiated groups. But at 3 and 6 months after 10Gy and 30Gy irradiated rats, there MBP content were in 50-62μg/mL level, which were a significant decrease compared with the control groups （p〈0.01）. Typical demyelination in corpus callosum of rats was observed in 30Gy irradiation after 6 months, but no evidence of demyelination was seen in all the other rats. The ultra-structural changes of myelin and oligodendrocytes were detected in 10Gy and 30Gy exposure after 1 to 6 months observed by electron microscope. All the demyelination changes were seen correlated with the dosage and duration after irradiation. These findings indicate that the radiation-related molecular and pathological characteristic changes of demyelination can be assessed in 3 to 6 months after single 10Gy to 30Gy whole-brain irradiation in SD rats.

关 键 词：电离辐射 大脑 脱髓鞘 髓鞘碱性蛋白 大鼠 

分 类 号：R818.74[医药卫生—放射医学]