不同reelin基因型小鼠大脑皮层分布的差异

Differences of the cerebral cortex in mice with different reelin genotypes

目的:比较分析不同reelin基因型小鼠大脑皮层分布的差异,为reelin在小鼠大脑皮层形成过程中的作用研究提供依据;方法:选择reelin杂合子小鼠繁殖后代,在出生10d时进行基因型鉴定,设reelin^(+/+)、reelin^(+/-)和reelin^(-/-)3组。每组取3只小鼠,采用DAPI染色细胞核,用荧光免疫组化标记FoxP-1、Tbr-1、NeuN和GFAP特异性表达的细胞,显微镜下观察拍照后进行结果分析;结果:从DAPI染色的细胞核及FoxP1、Tbr1、NeuN和GFAP标记的细胞显示,3种不同基因型小鼠大脑皮层结构彼此都存在一定差异,reelin^(+/-)型与reelin^(+/+)型小鼠相比大脑皮层结构相似,但也存在一定差异,如被FoxP-1和Tbr-1标记的神经元在SVZ区reelin^(+/-)型比reelin^(+/+)型更多;但reelin^(-/-)型与reelin^(+/+)型小鼠相比,reelin^(-/-)型小鼠大脑皮层无明显层的结构,FoxP-1、Tbr-1、NeuN和GFAP标记的细胞分布在整个皮层;结论:Reelin表达的下调或缺失对小鼠大脑皮层正常结构的形成存在影响,在reelin缺失表达后小鼠大脑皮层的形成明显发生异常,不具有典型的分层结构。

Objective： The differences of the cerebral cortex in mice with different reelin genotypes were analyzed by comparing nerve cell marker, which provides a scientific basis for the study of the role of reelin during formation of mouse brain cortical layers. Methods： Heterozygous reelin mouse offsprings were used, and genotype identification was performed 10 days after birth. The mice were divided into three groups including reelin＋/＋ , reelin＋/- and reelin-/- group, and each group had 3 mice. DAPI was used to stain nuclei, and fluorescence immunohistochemistry was performed to label FoxP-1, Tbr-1, NeuN and GFAP specific expression cells, then fluorescence microscope was used for further observation and analysis. Results： From the DAPI staining nuclei and FoxPq, Tbr-1, NeuN and GFAP labeling cells, they could be seen that there were some differences in the cerebral cortex layer structure among three different genotypes of mice. The cerebral cortex of reelin＋/ and reelin＋/＋ type mice had similar structure; there were some differences, such as more FoxP-1 and Tbr-1 labeled neurons in the SVZ region of reelin＋/- type than reelin＋/＋ type, and no obvious layer structure in the cerebral cortex of reelin-/- type mice, Tbr-1, NeuN, FoxP-1 and GFAP labeled cells distribution in all layers of the cortex. Conclusion： The down-regulation or the absence of reelin expression has obvious effect on normal formation of mouse cerebral cortex. Under the condition of reelin knock out mouse, the cerebral cortex is obviously abnormal and there is no typical layer structure.