Tg-SwDI/B小鼠空间记忆能力与脑内β淀粉样蛋白分布的研究

摘要

Objective:To observe the spatial memory and it’s relationship with distribution of amyloid-βprotein deposition in the Tg-SwDI/B mice brain. Methods:There were 20 homozygous Tg-SwDI/B and wild-type C57BL/6 male and female mice at the age of 12 months individually. Radial arm maze was used to test the spatial memory of all the mice, and thioflavine-S and glia fibrillary acidic protein (GFAP) were stained to study the distribution of Aβand astrocytes. Results:The spatial memory of Tg-SwDI/B mice was impaired obviously at the age of 12 months. Numerous fibrillar Aβwas accumulated in and around microvessels, and GFAP-positive reactive astrocytes were significantly elevated in all brain regions of Tg-SwDI/B mice, particularly in the hippocampal and thalamic regions. No deposits of fibrillar Aβwas observed in the brain of wild type C57BL/6 mice. Few GFAP-positive astrocytes were observed compared with those in Tg-SwDI/B mice. Conclusion:Spatial memory of Tg-SwDI/B mice was impaired, the microvascular fibrillar Aβdeposit and activated astrocytes proliferation in hippocampal region perhaps associated with the defect of spatial memory.%　　目的：观察Tg-SwDI/B小鼠空间记忆能力与脑内β淀粉样(Aβ)蛋白分布的情况。方法：12月龄纯合子Tg-SwDI/B小鼠和野生型C57BL/6各20只，雌雄比例为1颐1；通过八臂迷宫检测小鼠的空间记忆能力，硫磺素-S染色和GFAP免疫荧光染色显示Aβ及星形胶质细胞在小鼠脑内的分布特点。结果：Tg-SwDI/B小鼠空间记忆功能明显受损，表现为长期记忆功能下降，脑内有大量纤维化Aβ沉积在血管或其周围，并且可见GFAP阳性星形胶质细胞，两者均在海马和丘脑区域更为多见。同月龄野生型小鼠脑内未见纤维化Aβ沉积，存在少量GFAP阳性星形胶质细胞，但数量明显少于Tg-SwDI/B小鼠。结论：Tg-SwDI/B小鼠的空间记忆功能受损，可能与海马区域血管相关性纤维化Aβ和活化的星形胶质细胞增生相关。