神经元核抗原NeuN在C57BL/6小鼠垂体表达及分布

NeuN expression and distribution in hypophyseal structures in C57BL/6 mice

目的观察神经元核抗原(NeuN)在C57BL/6小鼠垂体的表达及分布。方法 8周龄C57BL/6小鼠4只,经心脏灌注取垂体,常规固定石蜡包埋切片,行NeuN及ACTH免疫荧光染色。脑组织冰冻切片,行NeuN免疫荧光染色。另有2只小鼠垂体行蛋白质印迹检测NeuN。结果 NeuN表达在垂体前叶细胞核膜及核仁,在垂体中叶则位于细胞核内,而在垂体后叶无明显表达;NeuN在皮质神经元则主要表达于胞质。蛋白质印迹显示皮质中46kD、48kD及66kD水平三条带,垂体组织可见一66kD分子量水平条带。结论 66kDNeuN为较特异表达于小鼠垂体组织细胞核的NeuN,其表达和分布差异可能与垂体前叶、中叶衍化和功能分化有关。

Objective To investigate NeuN expression and localization in mouse hypophyseal structures.Methods C57BL/6 mice,with an age of 8 weeks were utilized.Four animals were fixed by intracardial perfusion of 4% polyformaldehyde in PBS.Pituitary tissues were subjected to double immunofluorescence for NeuN and ACTH,whereas brain tissues undertook NeuN staining.Immunoblot was also employed for NeuN expression in 2 pituitaries.Results As a positive control,cerebral cortical neurons mainly showed cytosol expression of NeuN.NeuN was found localized in both nuclear membrane and nucleoli of almost all cells in the anterior pitutiary lobe,and in the intermediate pituitary lobe,it was localized within the nuclear body.In contrast,no significant fluorescence signal was found in the posterior pituitary lobe.In addition to the 46 kD and 48 kD bands in mouse cortex,a 66 kD band was concurrently detected in both pituitary and cortex.Conclusion The 66 kD NeuN is a relatively specific form in the mouse pituitary.It is differentially expressed and distributed in hypophyseal structures in the mouse,which may contribute to its distinct roles in hypophyseal development and function differentiation.