MODEL OF NERVE FIBER REGENERATION IN CNS BY EXCIMER LASER

准分子激光中枢神经系统神经纤维再生模型

基本信息

批准号：
02557002
负责人：
IDE Chizuka
金额：
$ 8.45万
依托单位：
KOBE UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1992
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02557002/
关键词：
excimer laser rat spinal cord CNS regeneration axon myelin sheath guide system dissecting microscope Kr-F 神経再生エキシマレ-ザ-中枢神経脊髄後索錐体路視神経組織修復

项目摘要

Excimer laser is characterized by being able to cut the tissue by photochemical effect without giving any destortions or hazardous thermal damages to the surroundings. This fact indicates that the laser-cut tissuemight be readily repaired.We applied excimer laser to cut the spinal cord in order to examine whether the laser-cut dorsal funiculus can be repaired much better than the spinal cord injured by knife or freezing. In addition, we made a guide system which conducts the laser beam to the dissecting microscope for cutting minute areas under direct observations.The laser is Kr-F laser with the wave length of 248 nm. The energy density per pulse, pulse frequency and irradiation area are 30 mJ/pulse, 5 Hz x 1 sec, 16mm x 0.2mm, respectively. Therefore, the energy density per area is 4.69J/cm^2. The depth of the lesion was about 100mum.Nerve fibers are cut sharply. Glia cells and myelin sheaths are severely damaged in the area adjacent to the lesion. The repair processes are observed during 3-28 days post-lesion. About 1 week post-lesion, non-myelinated axons, growth cones, glia cells and Schwann cells are found in the areas of lesion. Axons are later surrounded by myelin sheaths. Many blood vessels are formed in the lesion.The guide system of excimer laser was made. We are using it to cut confined small areas under dissecting microscope. Altough there are many points to be improved, the guide system of excimer laser is considered to be promising for the experimental model of CNS regeneration.

准分子激光的特点是能够通过光化学效应切割组织，而不会对周围环境造成任何变形或危险的热损伤。这一事实表明激光切割的组织可能很容易修复。我们应用准分子激光切割脊髓，以检验激光切割的背索是否可以比刀或冷冻损伤的脊髓更好地修复。此外，我们还制作了一个引导系统，将激光束引导至解剖显微镜，在直接观察下切割微小区域。激光为Kr-F激光，波长为248 nm。每个脉冲的能量密度、脉冲频率和照射面积分别为30mJ/脉冲、5Hz×1秒、16mm×0.2mm。因此单位面积的能量密度为4.69J/cm^2。病灶深度约100微米，神经纤维被锐利切断。病变附近区域的神经胶质细胞和髓鞘严重受损。在损伤后 3-28 天内观察修复过程。病变后约1周，病变区域发现无髓鞘轴突、生长锥、神经胶质细胞和雪旺细胞。轴突随后被髓鞘包围。病灶内形成大量血管。制作了准分子激光引导系统。我们用它在解剖显微镜下切割有限的小区域。尽管还有很多需要改进的地方，但准分子激光引导系统被认为对于中枢神经系统再生的实验模型很有希望。