APP/PS1双转基因小鼠的繁育、鉴定及评价

Reproduction,genotype identification and evaluation of APP/PS1 transgenic mice

目的:评价APP/PS1双转基因小鼠基因表达及认知行为能力的变化,为AD的相关研究提供有效的动物模型。方法:采用雄、雌鼠1:1合笼配对的方式,令APP/PS1双转基因小鼠自然交配进行繁育。PCR鉴定APP/PS1双转基因鼠仔鼠的基因型后,选择APP/PS1阳性小鼠作为模型(AD)组,同批APP/PS1阴性为对照(CT)组,每组8只小鼠。以Morris水迷宫实验检测仔鼠的空间学习记忆能力,以HE染色、刚果红染色观察仔鼠脑片组织病理学改变。结果:(1)APP/PS1双转基因鼠仔鼠基因经PCR扩增,出现约360 bp的目的基因条带,表明成功繁育出转入APP/PS1基因的仔鼠;(2)Morris水迷宫实验结果显示,与7月龄阴性小鼠(CT组)比较,同月龄的双转基因AD组小鼠的空间学习记忆能力明显降低(P<0.05);(3)HE染色结果显示,AD组小鼠海马结构及细胞形态出现明显异常;刚果红染色结果显示,AD组小鼠脑片组织出现β淀粉样蛋白斑块沉积。结论:APP/PS1双转基因小鼠较好地模拟了AD的病理变化及行为学特征,可作为研究AD发病机制及开发AD防治药物的实验工具。

Objective： To identify the genotype of（ APP/PS1） transgenic mice and evaluate the changing of cognitive and behavioral functions,provide an effective animal model for the Alzheimer＇s disease（ AD） research. Methods： Male APP/PS1 transgenic mice mated with female APP/PS1 transgenic mice,and the genotype of their filial mice was identified by PCR. The APP ＋/PS1 ＋mice were assigned into AD model group（ AD group,n = 8）,and the APP-/PS1-mice were assigned into control group（ CT group,n= 8）. The Morris water maze test was carried out to detect the capacity of learning and memory of mice. After that,the mice were sacrificed and the brain tissues were sampled and stained by HE and congo red for the pathological examination. Results：（1）A APP/PS1 genome DNA about 360 bp size was detected. The methods of feeding and breeding were successful to attain APP/PS1 transgenic mice.（2）Statistical significance was found in the differences of the capacity of learning and memory between 7-month-old APP/PS1 positive mice and negative mice（ P〈0. 05）.（3）The results of HE stain showed that the structure and cellular morphology of hippocampus of AD mice were obviously abnormal. The results of congo red stain showed that positive amyloid plaque was observed in brains of AD mice.Conclusion： APP/PS1 transgenic mice present typical symptoms and behaviors of Alzheimer＇s disease. The transgenic mouse is an effective tool for the research and prevention of AD.