C57/BL6小鼠海马结构发生、发育和衰老过程中的细胞增殖

摘要

Objective:To investigate the cell proliferation during the development and aging of C57/BL6 mouse hippocampal formatioa Methods: Immunohistochemistry, stereological methods and Western blotting were used to morphologically ob serve and quantitatively analyze the cell proliferation of C57/BL6 mouse hippocampal formation at different stages. Results: A large number of immunoreactive cells was seen in the hippocampal primordium at E12 d. At E18 d, immunoreactive cells differed at various layers. During P1-P14 d,positive cells were located at the exterior of pyramidal layer as a compact zone. It was the widest at P1 d but disappeared at P14 d. During P1-P7 d, positive cells were differed at every layer of DG. At P14 d, immunoreactive cells were mainly located at the 1/2 of the granular layers. During P28 d-18 M, positive cells were mainly differed at the subgranular layers. P1d-P3 d volume of CA pyramidal layer increased but decreased at P7 d. Volume of DG granular layer increased during P1 d-P14 d, but decreased during P21 d-18 M. The Vv of positive cells in CA pyramidal layer decreased in CA3 areas but increased in CA1 at P1d. At P7 d, it decreased in all areas. The expression of DCX protein increased from E18 d to P3 d, but decreased during P3 d-18 M. Conclusion-.There is a cell proliferation, differentiation and immigration peak in CA of mouse hippocampal formation during embryonic period, but still other peaks in DG during postnatal two weeks.%目的:探讨C57/BL6小鼠海马结构发育及衰老过程中细胞增殖的变化规律.方法:采用免疫组织化学和免疫印迹结合体视学方法对不同发育阶段C57/BL6小鼠海马结构中的细胞增殖进行系统观察和定量分析.结果:胚胎12天(E12 d)海马结构原基中见大量双皮质素抗原(DCX)阳性细胞.E18 d阳性细胞弥漫分布.生后1～14天(P1 d～P14 d)阿蒙角(CA)锥体层外周阳性细胞排列成1条致密带,P1 d最宽,至P14 d消失.P1 d～P7 d阳性细胞弥散分布于齿状回(DG)各层,P14 d主要分布于颗粒层内1/2,P21 d～18个月主要分布于亚颗粒细胞层.CA锥体层体积P1 d～P3 d呈上升趋势,P7d降低.DG颗粒层体积P1 d～P14 d增大；P21 d～18个月呈下降趋势.CA各区锥体细胞层阳性细胞Vv值P1 d CA3区下降,CA1区上升,P7d各区均降低.E18 d～P3 d,DCX蛋白表达逐渐增多；P3 d～18个月呈下降趋势.结论:小鼠海马结构细胞增殖、分化、迁移高峰,CA区位于生前,DG区生后两周仍有一高峰.