重症肌无力被动转移小鼠腓肠肌运动终板的形态学研究

Morphologic research on end plate in gastrocnemius muscle of experimental autoimmune myasthenia gravis mice

目的:观察重症肌无力(MG)小鼠腓肠肌运动终板的形态学变化,并改良运动终板处光镜及电镜下的制作方法。方法:采用AChR单克隆抗体mAb35腹腔注射C57BL/6幼年小鼠,建立MG被动转移模型。采用Karnovsky-Roots法行乙酰胆碱酯酶组织化学染色,并在电镜下观察小鼠腓肠肌运动终板超微结构处形态学改变。结果:小鼠注射mAb35后出现肌无力症状与MG患者表现相似;Karnovsky-Roots法染色后可见沿神经末梢分布的运动终板;实验组腓肠肌运动终板处超微结构发生病理改变,此种改变符合MG神经肌接头处运动终板的病理改变。结论:Karnovsky-Roots法显示乙酰胆碱酯酶简便、经济;而电镜检查是确定PTMG模型运动终板超微结构有无病理改变的最佳方法。二者结合可为今后有关MG运动终板的病理研究提供一种可靠的方法。

Objoctive： To study the pathological characteristics of end plate in gastrocnemius muscle of experimental autoimmune myasthenia gravis animal model under light and electron microscopes. Methods： Passively transferred myasthenia gravis （PT, MG）animal model on C57BL/6 mice aged 4 to 5 weeks was induced by injecting acetylcholine receptor monoclonal antibody mAb35, and the ultrastructure of end plates was studied by acetylcholinsterase histochemical technique of Kamovsky-Roots. Results： Myasthenia symptoms were induced in the experimental group. The end plates in gastrocnemius muscle showed ultrastructural changes similar to those of myasthenia gravis patients but no change was found in the number of the end plates. No changes were observed in the control group. Conclusions： The animal model shows ultrastructural changes of end plates in gastrocnemius muscle. The acetycholinsterase histochemical technique of Kamovsky-Roots is convenient and economic. The ultrastructural study is valuable for exploring pathomorphism changes of PTMG, as well morphological changes of end plate.