He-Ne激光对脑细胞损伤影响的实验研究

目的 采用He-Ne激光直接照射大鼠颅骨缺损部位的脑组织，观察He-Ne激光对脑损伤早期组织形态学，代谢，功能的影响。方法 66只Wistar大鼠随机分为A，B，C，D，E，F六组，均在麻醉下去除部分颅骨制作脑 损伤模型。采用波长为632.8nm，输出功率25mW的He-Ne激光照射脑组织，光斑直径2cm，照射距离70cm，A，B，C为即刻观察组；E，F为1周观察组。取损伤侧脑组织和血浆分别损伤侧脑组织及血浆中丙二醛（MDA）的含量和超氧化物歧化酶（SOD）的活性。光镜观察脑组织形态学变化；评定1周观察组大鼠处理前后平衡及支撑时间的改变。结果 即刻观察组中各激光照射组与对照组形态观察未见明显差异，经组间配对t检验发现，A，B，C组与D组之间进行比较血浆中MDA值明显降低（P＝0．000），血浆中SOD值无显著性差异；1周观察组中治疗组血浆MDA值较对照组明显减少（P＝0．001），大鼠平均时间（P＝0．02）和支撑时间（P＝0．0016）较对照组有明显提高。结论 不同剂量He-Ne激光的即刻照射对大鼠脑组织的形态学改变，脑组织中的MDA／SOD和血浆中的SOD改变影响不大；1周He-Ne激光直接照射可降低脑损伤大鼠血浆和脑组织MDA含量，增强血浆中SOD的活性，改善肢体平衡和支撑功能。

Experimental study of the effect of He-Ne laser irradiation on injured brain injuries in rats

Objective To evaluate the effect of low energy He Ne laser irradiation on the injuried brain tissues in rats. Methods Models of brain injury were made with sixty six Wistar rats which were randomly allocated into 6 groups(A F). The brain tissues of the rats in groups A to C received the He Ne laser irradiation for 1, 3 and 5 min, respectively, and were observed immediately after the irradiation, while the rats in groups E and F observed one week later, the rats in group D served as control. Results There was no significant difference with morphological changes and plasma level of SOD among the rats in groups A to C and those in groups D, but the plasma level of MDA in groups A to C was significantly lower than that in group D ( P <0.001). After laser treatment, the plasma level of MDA was obviously lower than that of group D ( P =0.001), while the level of plasma SOD was significantly increased ( P =0.001). The MDA level in the laser irradiated brain tissues was also lower than that in the control group( P =0.001). Conclusion He Ne laser irradiation can reduce the MDA level both in the plasma and injuried brain tissues, and increase the activity of SOD in plasma.