阿尔茨海默病转基因小鼠高场强磁共振影像学与病理学对照研究

目的 观察和分析转基因阿尔茨海默病(AD)小鼠模型早期的脑部影像学特征,确立7.0 T高场强磁共振显微成像(MRMI)对于早期AD的诊断价值.方法 3、6、9个月龄的APP/PS-1转基因小鼠各6只作为实验组,同龄野生型小鼠作为对照组;应用Bruker Phama Scan 7.0 T磁共振仪对小鼠脑部进行扫描;成像后取小鼠脑组织切片经β-淀粉样蛋白(Aβ)免疫组织化学染色,并与脑部的T2WI进行对照.结果 随着月龄的增加,APP/PS-1转基因小鼠脑部的Aβ沉积加剧,在6个月龄的APP/PS-1转基因小鼠脑部切片上已有Aβ斑块的形成,而9个月的APP/PS-1转基因小鼠皮质和海马内Aβ沉积斑块数量增多;9个月龄实验组小鼠海马及皮质可见散在点状低信号区,分布范围与病理改变相符;3、6个月龄APP/PS-1转基因小鼠及3组各月龄对照组小鼠脑组织结构T2WI未见明显低信号区.结论 与Aβ免疫组化病理结果对照,7.0T高场强MR能够显示9个月龄APP/PS-1转基因小鼠脑部的Aβ斑块沉积,有助于早期AD的诊断.

Abstract：

Objective To observe and investigate the neuroimaging characters in early progression of transgenic Alzheimer's disease (AD) mice model, and make sure the diagnosis value of 7.0 T high field magnetic resonance microimaging(MRMI). Methods APP/PS-l transgenic mice aged 3,6, 9 months and the same aged wild type mice were each divided into 6 groups(6 mice in every groups) based on age. The mice brains were scaned with 7.0T high magnetic field MR. Then the mice were killed. The Aβ immunohistochemistry examination was analyzed in the mice brains specimens, and pathological changes were in comparison with the T2 weighted imaging in the mice brains. Results There were a few Aβ plaques in the brains of 6 months APP/PS-1 transgenic mice, while Aβ plaques were increased both in number and volume in the cerbral cortex and hippocampus of 9 months AD mice. The brains of APP/PS-1 double transgenic mice of 3, 6 months and the control group mice were not showed intensity loss on T2 weighted MR images, while the signal intensity loss was visualized in the cerbral cortex and hippocampus of 9 months AD mice. Conclusion 7. 0T high magnetic field MR could display Aβ plaques in the brains of APP/PS-1 double transgenic mice of 9 months and it is helpful to diagnosis early AD.

The comparative study on high field MRI and pathology of Alzheimer's disease transgenic mice

Objective To observe and investigate the neuroimaging characters in early progression of transgenic Alzheimer's disease (AD) mice model, and make sure the diagnosis value of 7.0 T high field magnetic resonance microimaging(MRMI). Methods APP/PS-l transgenic mice aged 3,6, 9 months and the same aged wild type mice were each divided into 6 groups(6 mice in every groups) based on age. The mice brains were scaned with 7.0T high magnetic field MR. Then the mice were killed. The Aβ immunohistochemistry examination was analyzed in the mice brains specimens, and pathological changes were in comparison with the T2 weighted imaging in the mice brains. Results There were a few Aβ plaques in the brains of 6 months APP/PS-1 transgenic mice, while Aβ plaques were increased both in number and volume in the cerbral cortex and hippocampus of 9 months AD mice. The brains of APP/PS-1 double transgenic mice of 3, 6 months and the control group mice were not showed intensity loss on T2 weighted MR images, while the signal intensity loss was visualized in the cerbral cortex and hippocampus of 9 months AD mice. Conclusion 7. 0T high magnetic field MR could display Aβ plaques in the brains of APP/PS-1 double transgenic mice of 9 months and it is helpful to diagnosis early AD.