大鼠海马注射β淀粉样蛋白建立记忆障碍模型的研究

Study of rats with β-amyloid injection into hippocampus

目的 建立记忆障碍大鼠模型 ,探讨 β淀粉样蛋白 (Aβ)的在体毒性作用。 方法 给大鼠双侧海马CA1区定向注射Aβ1 4 0 (模型组 ) ,注射生理盐水的大鼠作为对照组 ,并设立正常对照组和假手术对照组。 2周后各组大鼠均作Y型迷宫测试后进行苏木素 伊红、刚果红、尼氏染色及乙酰胆碱脂酶 (AChE)组化染色等病理学观察。采用方差分析和t检验对量化指标行统计分析。结果 模型组大鼠AChE阳性纤维密度及空间学习、记忆能力均明显低于各对照组 ;其海马CA1区锥体细胞带损伤长度为 (1 94± 0 2 3)mm ,生理盐水对照组为 (0 35± 0 0 7)mm ,差异有非常显著性 (P <0 0 1)。结论 双侧海马注射Aβ1 4 0 可建立一种简易的记忆障碍动物模型 ,尤其是对研究Aβ毒性机制及防治具有更强的针对性。

Objective To establish an animal model for Alzheimer′s disease (AD) and to observe the neurotoxic effects of β amyloid (Aβ) in vivo Methods The rats were divided into four groups The model group was administered Aβ 1 40 into bilateral CA 1 subregion in hippocampus The control group was administered saline in the same way Sham operation group and normal group were set up as additional control All the rats in various groups were tested with Y maze two weeks after injection H&E, Congo Red staining, Nissle staining, and the histochemical method for acetylcholinesterase (AChE) were used to detect the histological changes in hippocampus The data were analyzed with One Way Analysis of Variance and T Test Results The model rats showed lesser AChE positive fibers density in hippocampus and worse ability in learning and memory compared with those of control rats The length of lesion in CA 1 pyramidal cell layer was (1 94±0 23) mm after Aβ 1 40 injection and (0 35±0 07) mm after saline injection, which was significantly different (P<0 01) between the model group and control group Conclusions Rats injected with Aβ 1 40 into hippocampus may be a kind of useful AD model, especially in the study of neurotoxic effects of Aβ and treatment of AD