Basic study of heavy-ion irradiated to the normal brain tissue -Effects of carbon particles exposure to rat's hypothalamus on the spontaneous motor activity-

重离子照射正常脑组织的基础研究-碳粒子照射大鼠下丘脑对自发运动活动的影响-

基本信息

批准号：
17591249
负责人：
UNO Takashi
金额：
$ 2.24万
依托单位：
Chiba University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2006
项目状态：
已结题

项目摘要

Radiation therapy is applied to several brain tumors. It is expected that irradiation to the brain, especially in younger age, gives some adverse effects. Heavy-ion beams are more effective to treat brain tumors than ordinary X-rays. However, the effect of heavy-ion irradiation to brain on spontaneous motor activity is not reported. This study was designed to determine whether irradiation (carbon particles 290 MeV/nucleon, mono peak 60Gy, irradiation field 5 mm^2 in midbrain) to rat's hypothalamus modifies the spontaneous motor activity of male rats.The irradiation field in rat's brain after carbon particles irradiation was identified by imaging plate method. The spontaneous motor activity was determined with the wheel-running test. The activity was measured using an active increase effect of methamphetamine (MAP). The observation of wheel-running activity was conducted for 90 min after 2, 6, 14, 22, 26 or 30 weeks following irradiation.Results are as follows.The control group and irradiated group were highest motor activity in wheel-running test at first test ( 1^<st> injection of MAP, 2 weeks after irradiation) ; however, motor activity of the control group decreased after from 2^<nd> test (6 weeks) to 5^<th> test (22 weeks). On the other hand, 60 Gy exposed rats were not decrement of wheel-running activity which depended on number of times in motor activity test (injection time of MAP). These results may be possible to describe that carbon irradiation to hypothalamus is caused edema at the irradiated field. Furthermore, it was supposed that an ambient blood flow increased to make up for disordered hemodynamics by the edema.

放射疗法应用于几种脑肿瘤。预计对大脑的照射，尤其是在年轻人时代，会产生一些不利影响。与普通X射线相比，重离子束治疗脑肿瘤更有效。然而，尚未报告对大脑对大脑自发运动活动的影响。这项研究旨在确定辐射（碳颗粒290 MeV/核，单核，单峰60gy，辐照场5 mm^2）在大鼠的下丘脑中是否会通过碳颗粒辐照后大鼠脑的自发性运动来修饰大鼠脑的自发性运动活性。通过轮毂测试确定自发运动活动。使用甲基苯丙胺（MAP）的主动增加效应来测量活性。在辐照后2、6、14、22、26或30周后，进行了轮毂活动的观察90分钟。结果如下。对照组和辐照组在第一次测试时进行了车轮运行测试中的最高运动活性（1^<st i辐射后2周，在辐照后2周）；但是，对照组的运动活性从2^<nd>测试（6周）降低到5^<th>测试（22周）。另一方面，60 Gy暴露的大鼠并不降低车轮运行活动，这取决于运动活动测试的次数（地图的注射时间）。这些结果可能可以描述对下丘脑的碳照射在辐照场引起的水肿。此外，据认为，环境血流增加以弥补水肿的无序血流动力学。