Nbn基因对出生后小鼠海马发育的影响

Effect of Nbn gene on hippocampus development in postnatal mice

目的通过观察神经特异性Nbn基因敲除(Nbn-CNS-Del)和对照(Nbn-CNS-Ctr)小鼠海马发育的形态学变化,探讨DNA损伤修复基因Nbn在生后小鼠海马发育过程中的作用。方法应用光镜连续切片和体视学方法对生后(postnatal day,P)7、14、21 d的实验组和对照组小鼠海马进行系统地形态学观察和定量分析。结果Nbn-CNS-Del小鼠海马发育比Nbn-CNS-Ctr明显滞后,至P21 d椎体层和齿状回(DG)颗粒层的截面面积均减小(P<0.05),DG颗粒层和多形层及CA4区的体密度差异均有统计学意义(P<0.05)。结论DNA损伤修复基因Nbn是小鼠海马发育的一个重要基因,影响小鼠海马椎体层成熟和DG颗粒细胞的发育与成熟。

Objective To investigate the role of neuro-specific DNA repair gene Nbn in mouse hippocampus development by observing the morphological differences in Nbn-CNS-Del and Nbn-CNS-Ctr mice. Methods Serial sections and stereology were used to quantitatively analyze the development of mouse hippocampus on postnatal day 7, 14 and 21. Results Compared with that of.the control group, the hippocampus development of Nbn-CNS-Del mice lagged behind. In Nbn-CNS-Del mice, on day 21, the profile area of pyramidal layer of hippocampus and granular layer of dentate gyrus decreased （P〈0.05）, and the volume densities in granular layer and polymorphic layer of dentate gyrus, and CA4 had significant differences （P〈O. 05）. Conclusion DNA repair gene Nbn, an important gene in mouse hippocampus development, affects the development and maturation of hippoeampus and granular layer of DG in mice.