内质网应激因子 ATF6在 hSOD1G93A 转基因小鼠脊髓中的表达

摘要

目的：应用目前国际公认的肌萎缩侧索硬化（ALS）发病机制及临床前药物研究的动物模型hSOD1G 93A转基因小鼠，初步研究 hSOD1G 93A小鼠脊髓中是否存在内质网应激中活性转录激活因子（ATF6）信号通路的激活，进而探究内质网应激在 ALS 发病机制中的作用。方法① hSOD1G 93A转基因小鼠及其同窝对照组小鼠的获得；②应用免疫组织化学方法观察转基因小鼠组和对照组显示脊髓前角运动神经元 ATF6阳性细胞数量。结果症状早期和终末期转基因小鼠（分别为105～115d 和120～130d），较对照组和无症状组转基因小鼠（60d）ATF6进入细胞核的运动神经元数量明显增多，差异有统计学意义（P＜0．05）；症状早期和终末期相比较差异无统计学意义（P＞0．05）；症状早期和终末期的一些细胞形态发生改变，出现皱缩，终末期运动神经元的数目减少。结论在无症状组时没有发现内质网应激因子 ATF6的改变，但在疾病症状早期出现明显 ATF6的改变，并随着疾病的进展而加重，说明内质网应激参与了 ALS 的发病，同时终末期脊髓前角运动神经元数量大幅减少。%Objective hSOD1G 93A transgenic mice is the most widely used ,as the internationally recognized ALS pathogenesis and pre-clinical drug research in animal models .To observe the changes of endoplasmic reticulum stress factor ATF6 in transgenic mice hSOD1G 93A spinal cord motor neuron, and then explore the role of endoplasmic reticulum stress in the pathogenesis of ALS .Methods The first part: hSOD1G 93A transgenic mice and littermate control mice received.The second part: Immunohistochemical method was used to display the number of spinal cord motor neuron(MN) of ATF6 into the nucleus in different groups .Rseults ①The experimental animals were divided into hSOD1G 93A transgenic mice and negative mice by PCR ;②Symptoms early group and end -stage group compared with control and asymptomatic group , the number of motor neurons were significantly increased which ATF 6 was into the nucleus.It had statistically significant;but the number of positive cells was not significantly changed between early symptoms and end-stage;ATF6 expressed in motor neurons cytoplasm at the control group and asymptomatic group ,the two groups was not significantly compared ;and ATF6 were observed in the nucleus at the early symptoms ;③Some of the motor neurons morphology changes at the early symptoms and end -stage,shrinkage,the number of end-stage motor neurons greatly reduced .Conclusion In the asymptomatic group (60 days) find an endoplasmic reticulum stress factor ATF6 change.In early symptoms of ALS disease ATF6 change significantly and increased as the disease progresses.It is indicated that endoplasmic reticulum stress participate in the pathogenesis of ALS .However,the clear pathogenesis of ALS needs further study .