DMT1在APP/PS1转基因小鼠大脑皮层老年斑内的定位研究

目的研究二价金属离子转运体1(divalent metal transporter 1,DMT1)在APP/PS1转基因小鼠大脑皮层内的定位分布,探讨DMT1异常表达影响脑铁代谢平衡从而参与AD发病的可能机制。方法应用免疫组织化学方法观察DMT1在9月龄APPsw/PS1小鼠大脑皮层的阳性分布;应用免疫荧光双标技术和共聚焦激光扫描显微镜观察DMT1蛋白和β淀粉样蛋白(β-amyloid peptide,Aβ)在APP/PS1转基因小鼠大脑皮层老年斑内的一致性分布和位置关系。结果APP/PS1转基因小鼠大脑皮层老年斑内均有DMT1阳性表达;DMT1和Aβ免疫双标发现DMT1免疫阳性产物与Aβ共存于老年斑,二者分布具有一致性。结论DMT1在APP/PS1转基因小鼠大脑皮层老年斑内大量表达,其分布与Aβ具有一致性,提示DMT1可能参与AD脑内Aβ沉积和老年斑形成。

Localization of DMT1 in Cerebral Cortex of APP/PS1 Transgenic Mouse Brain

Objective To investigate the distribution and localization of divalent metal transporter 1(DMT1) in the cerebral cortex of APP/PS1 transgenic mouse, and to explore the possible role of DMT1 in Alzheimer disease (AD) pathogenesis. Method Immunohistochemistry, immunofluorescence and confocal laser scanning microscopy were used to analyze the distributions of DMT1 and β-amyloid protein (Aβ) and the relationship between these two proteins in cerebral cortex of APP/PS1 mouse. Results DMT1 immunoreactive product was seen to be localized in the senile plaques within the cerebral cortex of APP/PS1 transgenic mouse. Almost all of senile plaques presented DMT1 immunoreactivity with different expression. Confocal microscopic results revealed that a co-localization of DMT1 and Aβ was found in the senile plaques. Conclusion The abundant expression of DMT1 in Aβ senile plaques suggests that DMT1 may be involved in the deposition of Aβ and the formation senile plaque in AD brain.