EXPERIMENTAL STUDY OF RADIATION-INDUCED DEMENTIA -CHANGES IN GROWTH INHIBITORY FACTOR AFTER HEMICRANIAL IRRADIATION ON NEONATAL RAT BRAINS-

辐射诱发痴呆的实验研究-新生大鼠大脑半颅辐射后生长抑制因子的变化-

• 批准号: 06454411
• 负责人: MORII Ken
• 金额: $ 4.54万
• 依托单位: NIIGATA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06454411/
• 关键词: radiation; rat; GIF; GFAP; MAG; アポトーシス; 放射線障害; 水迷路; 受動的回避学習; 高次機能; m-RNA

To investigate radiation injury on normal brain in radiotherapy of brain tumors, the effects of X-irradiation on normal rat brain have been studied.1.Neonatal rats, aged 7 days, received single doses (5,7.5,10,15Gy) of X-irradiation to the right hemicranium. At 1,2,3,4, and 5 weeks after irradiation, the changes of mRNA of myelin-associated glycoprotein (MAG), neuron specific enolase (NSE) and S-100 protein were analyzed with Northern blotting technique. The level of expression of MAG mRNA in the irradiated hemisphere was significantly low compared with that in the unirradiated hemisphere at 1 week after radiation. The levels of NSE mRNA and S-100 mRNA in the irradiated hemisphere were as same as that in the unirradiated hemisphere after 1-5 weeks after radiation. The results suggest that oligodendroglias are more sensitive to irradiation than neurons and astrocytes.2.The changes of growth inhibitory factor (GIF) and glial fibrillary acidic protein (GFAP) after 15Gy hemicranial irradia … More tion were analyzed using Western blotting technique. The irradiated right hemispheres (IR), the non-irradiated left hemispheres (NIL) of the same 7-day-old rats, and the sham-irradiated right hemispheres (SIR) of the age-matched rats were examined for a period of 4 weeks postirradiation. The GIF relative level to sham control in IR was increased after irradiation, reached a maximum of 164% of the GIF level in SIR at 3 weeks postirradiation and remained at an increased level until at least 4 weeks, while the GFAP relative level to sham control in IR was increased after irradiation, reached a maximum of 152% of the GFAP level in SIR at 3 weeks postirradiation and then declined rapidly. These results indicate that GIF could play an important role in central nervous system repair following brain damage and may provide new insights into the mechanism of gliosis investigated mainly focusing on GFAP and of tissue reconstruction which is thought to be mainly controlled by neurotrophic factors.3.Apoptosis was examined with in situ apoptosis detection kit (Oncor corporation) at 2,3,6 hours, 1,3 and 5 days post-15Gy hemicranial irradiation. In the irradiated hemisphere apoptotic cells were found in the subcortical white matter, hippocampal dentate gyrus and subependymal layr of the lateral ventricle at 3 and 6 hours after irradiation. The results suggest that apoptosis is closely related with disturbance of cerebral white matter at the acute stage for the irradiation insult. Less

为探讨脑肿瘤放射治疗对正常脑组织的损伤，本实验研究了X线照射对正常大鼠脑组织的影响。1.对7日龄新生大鼠右侧颅骨进行单次剂量（5、7.5、10、15 Gy）X线照射。于照射后1、2、3、4、5周，采用北方印迹法检测髓鞘相关糖蛋白（MAG）、神经元特异性烯醇化酶（NSE）和S-100蛋白mRNA的变化。照射后1周，照射侧大脑半球MAG mRNA表达水平显著低于未照射侧大脑半球。照射后1-5周，照射侧脑组织NSE mRNA和S-100 mRNA水平与未照射侧脑组织相同。结果表明，少突胶质细胞对辐射的敏感性高于神经元和星形胶质细胞。2. 15 Gy照射后，少突胶质细胞生长抑制因子（GIF）和胶质细胞酸性蛋白（GFAP）的变化 ...更多信息 采用Western blotting技术分析。照射后4周，对相同7日龄大鼠的照射右半球（IR）、未照射左半球（NIL）和年龄匹配大鼠的假照射右半球（SIR）进行检查。IR组GIF相对于假手术对照组的水平在照射后升高，在照射后3周达到SIR组GIF水平的164%，并持续升高至少4周; IR组GFAP相对于假手术对照组的水平在照射后升高，在照射后3周达到SIR组GFAP水平的152%，然后迅速下降。这些结果表明GIF在脑损伤后中枢神经系统的修复中可能发挥重要作用，并可能为以GFAP为主的胶质细胞增生机制和以神经营养因子为主的组织重建机制提供新的见解（Oncor公司）于照射后2、3、6小时、1、3、5天处死动物。照射后3 h和6 h，照射侧半球皮质下白色质、海马齿状回和侧脑室室管膜下层可见凋亡细胞。结果提示：放射损伤急性期脑细胞凋亡与脑白色物质紊乱密切相关。少