氯化镁对大鼠坐骨神经断端再生微结构的作用研究

目的：研究氯化镁对大鼠坐骨神经损伤后超微结构修复的作用。方法将90只SD大鼠随机分为氯化镁组（MgCl2组），神经生长因子组（NGF组），0．9％氯化钠组（NaCl ）组，每组30只。制作坐骨神经缺损模型，分别以硅胶管桥接坐骨神经缺损，构成神经再生室。分别将1 mmol／L MgCl2、NCF、0．9％氯化钠溶液分别注入神经再生室中。于术后4、8、12周处死动物，取出神经再生室中断端再生组织，固定处理后通过光镜观察再生神经纤维数目及再生纤维神经截面积，电镜观察神经再生室中雪旺细胞增殖和发育情况、髓鞘的超微结构。结果 MgCl2组和NGF组术后4、8、12周再生神经纤维数目和再生神经纤维截面积高于NaCl组，差异有统计学意义（ P ＜0．05），而MgCl2组与NGF组比较，差异无统计学意义（ P ＜0．05）。 MgCl2组和NGF组新生神经纤维再生数量增多，雪旺细胞增生明显，形态接近正常，髓鞘厚度均匀增加，鞘层分离不明显，神经膜细胞及轴浆有轻度变性，NaCl组神经纤维再生不明显，髓鞘结构模糊，扭曲，雪旺细胞增生不明显，表型幼稚。结论氯化镁可促进大鼠坐骨神经损伤修复后超微结构的修复。

A experimental stud y on the effects of mgan esiumc hlro ide on ultrastructure renovation after scai tic nerve injury in rats

Objective To investigate the effects of magnesium chloride on ultrastructure renovation after sciatic nerve injury in rats .Method s Ninety SD rats were randomly divided into 3 groups: magnesium chloride group ( MgCl2 group ) , nerve growth factor group (NGF group), 0.9%sodium chloride group (NaCl group), with 30 rats in each group.Firstly,the animal models with sciatic nerve injury were established , and the injury was bridged with silicone tube to set up a nerve regeneration chamber (NRC),then 1mmol/L MgCl2,NCF,0.9% sodium chloride solution was infused into the chamber , respectively.After operation the rats were sacrificed on 4,8,12 weeks,respectively .The regenerating tissues in NRC were taken out to be fixed ,finally, the regenerating nerve fibers number and section area of regenerating nerve fibers were observed under light microscope ,moreover, the state of proliferation and development of Schwann cells in NRC and ultrastructure of medulla sheath was observed by electron microscopy .Results The regenerating nerve fibers number and section area of regenerating nerve fibers in MgCl2 group and NGF group on 4,8,12 weeks were significantly higher than those in Nacl group (P<0.05).However there were no significant differences between MgCl 2 group and NGF group ( P >0.05).In MgCl2 group and NGF group ,the regenerating nerve fibers number was increased ,the proliferation of Schwann cells was obvious and cell's shape was nearly normal ,the thickness of medulla sheath was uniformly increased .in contrast to that, in NaCl group, nerve fibers regeneration was not obvious , medulla sheath structures were blurred and twisted , the proliferation of Schwann cells was not obvious , with immature phenotype .Conclusion Magnesium chloride can promote the ultrastructure renovation after sciatic nerve injury in rats .