低强度He-Ne激光对兴奋性神经毒素所致小鼠神经元损伤的防护作用  

Protective Effect of the Low Level He Ne Laser on Damaged Neurons of Mice Induced by Excitatory Neurotoxin

作　　者：赵晓宁[1] 王瑜[1] 陶艳梅[1] 胡正荣[2] 张祖暄[1] 

机构地区：[1]南京大学医学院,210093 [2]东南大学电子工程系

出　　处：《中国激光医学杂志》1999年第4期220-224,共5页Chinese Journal of Laser Medicine & Surgery

基　　金：国家自然科学基金

摘　　要：目的　探讨低强度ＨｅＮｅ 激光对兴奋性神经毒素所致小鼠神经元损伤的防护作用，为低强度激光在临床上用于治疗脑功能障碍等神经系统疾病提供实验依据。方法　以兴奋性神经毒素谷氨酸（Ｇｌｕ） 或谷氨酸单钠（ＭＳＧ） 建立昆明系小鼠神经元损伤模型。在离体实验中观察了低强度ＨｅＮｅ 激光对原代培养的小鼠大脑皮层神经元形态结构及培养液中过氧化产物丙二醛（ＭＤＡ） 浓度的影响，同时也观察了小鼠大脑皮层单个神经元内游离钙（［Ｃａ２＋］ｉ）浓度在Ｇｌｕ 和激光作用下的变化。在体实验主要观察了激光对小鼠下丘脑弓状核神经元形态结构的影响。结果　离体实验结果表明，功率３ ｍＷ、能量密度２－３～３－４ Ｊ／ｃｍ２ 的ＨｅＮｅ 激光持续１０～１５ ｍｉｎ 照射原代培养的小鼠大脑皮层神经元，能减少培养液ＭＤＡ的释放，并能对抗由Ｇｌｕ 所致的皮层神经元损伤；以功率６ ｍＷ、能量密度２８－６Ｊ／ｃｍ２ 的ＨｅＮｅ 激光照射２－５ ｍｉｎ，还能降低小鼠大脑皮层单个神经元内由Ｇｌｕ 引起的［Ｃａ２＋］ｉ 升高。在体实验结果显示，以功率３ ｍＷ、能量密度１－７×１０４Ｊ／ｃｍ２ 的ＨｅＮｅ 激光每天１ 次血管内照射３０ ｍｉｎ，持续７ 天。Objective In this paper, the protective effect of low level He Ne laser on damaged neurons in mice induced by excitatory neurotoxicity (glutamic acid,Glu; monosodium glutamate,MSG) was studied. It has provided a scientific basis for the low level laser treatment of functional disturbance of brain. Methods The model of damaged neurons of mice(Qunming line) by use of Glu and MSG was made. Microscopic features of cortical neurons in primary culture and concentration of malondialdehyde(MDA) in medium by laser were observed in vitro. The intracellular free calcium concentration ([Ca 2+ ] i) of single neuron was simultaneously measured using Fura 2 under the action of Glu and laser. In vivo, the morphological changes of nucleus areas in the arcuate nucleus(AN) of mice were surveyed by laser.Results 1)In vitro, the low level He Ne laser (632 8 nm, 3 mW, 10～15 min, 2 3～3 4 J/cm 2) not only reduced the concentration of MDA in medium, but protected the damaged neurons of cortical primary cultures as well. At the same time, the laser (632 8 nm, 6 mW, 2 5 min, 28 6 J/cm 2) prevented the Glu induced elevation in [Ca 2+ ] i of single neuron. 2)In vivo, it was found that the laser ( 632 8 nm, 3 mW, 30 min, 1 7×10 4 J/cm 2/d) intravascular irradiation (once every day,for 7 days) could alleviate neuronal damages of the arcuate nucleus in hypothalamus induced by MSG and increase the areas, equivalent girth and diameter of the arcuate nucleus. Conclusions The results suggest that the low level He Ne laser plays a marked role in protecting damaged neurons in mice induced by excitatory neurotoxin Glu or MSG.

关 键 词：神经元 激光 谷氨酸 谷氨酸单钠 防护作用 

分 类 号：R454.2[医药卫生—治疗学]