肝脏X受体β对围生期小鼠海马细胞增殖以及放射状胶质细胞纤维形成的影响  

Liver X receptor β participates in cell proliferation and fiber formation of radial glial cells in hippocampal dentate gyrus of perinatal mice

作　　者：郭亮[1] 黄伟[1] 徐培[2] 范晓棠[2] 徐海伟[3] 

机构地区：[1]第三军医大学基础医学部生理学教研室,重庆400038 [2]第三军医大学基础医学部组织与胚胎学教研室,重庆市神经科学研究所,重庆400038 [3]第三军医大学西南医院全军眼科中心,重庆400038

出　　处：《第三军医大学学报》2011年第24期2545-2549,共5页Journal of Third Military Medical University

基　　金：国家重点基础研究发展计划(973计划,2010CB529403);国家自然科学基金(31071299)~~

摘　　要：目的观察肝脏X受体β(liver X receptorβ,LXRβ)对围生期小鼠海马细胞增殖以及放射状胶质细胞纤维形成的影响。方法在胚胎发育18.5 d(E18.5)和生后第2天(P2)行海马免疫组织化学方法检测,分别采用细胞增殖标记增殖细胞核抗原(proliferating cell nuclear antigen,PCNA),放射状胶质细胞或前体细胞标记Nestin以及放射状胶质细胞标记脑脂质结合蛋白(brain lipid binding protein,BLBP),比较野生小鼠和LXRβ敲除小鼠的表达差异。结果在小鼠E18.5和P2,LXRβ在海马有丰富表达;在小鼠E18.5,LXRβ敲除小鼠中海马齿状回PCNA细胞数量明显减少(P<0.01),BLBP标记的放射状胶质细胞纤维数量减少(P<0.05),胞体无明显改变(P>0.05)。P2与E18.5相比,PCNA阳性细胞数轻微增加,敲除小鼠与野生小鼠相比,PCNA阳性细胞数明显减少(P<0.05);BLBP标记的放射状胶质细胞胞体数量轻微增加,但敲除小鼠与野生小鼠相比,胞体数量无明显改变(P>0.05),纤维数量明显减少(P<0.05),在E18.5和P2,Nestin阳性细胞的分布与BLBP一致,但敲除小鼠中纤维出现断裂。结论 LXRβ参与围生期小鼠海马的细胞增殖以及放射状胶质细胞纤维形成。Objective To determine the effect of Liver X receptor β（LXRβ） on the cell proliferation and fiber formation of radial glial cells in hippocampal dentate gyrus（DG） of perinatal mice.Methods Embryonic 18.5 d（E18.5） and postnatal（P2） mice hippocampus was collected,and then immunohistochemical assay was used to detect the expression of the markers for cell proliferation（proliferating cell nuclear antigen,PCNA）,for radial glial cells（brain lipid binding protein,BLBP） and Nestin.The results of LXRβ knockout mice and WT controls were compared.Results LXRβ was strongly expressed in the hippocampus both at E18.5 and P2 of WT mice,of which densely stained positive cells mainly localized in the DG.At E18.5,LXRβ knockout mice showed the decreased number in the PCNA positive neurons（P0.01） and BLBP-labeled radial glial fibers（P0.05） when compared with WT mice,but,no change of the number of radial glial cell bodies was found（P0.05）.At P2,compared to E18.5,the number of PCNA positive neurons in the DG was slightly increased,which was decreased by LXRβ knockout（P0.05）.Moreover,the morphology of BLBP labeled radial glia cells in the DG at P2 was different from that in the DG at E18.5,of which the number of cell bodies was slightly increased,but radial glial fibers disrupted.LXRβ knockout induced significant decrease in the number of radial glial fibers（P0.05）,although did not affect the number of radial glial cell bodies in the DG（P0.05）.As another marker for radial glial cells,Nestin was expressed in the similar pattern to that of BLBP,but the nestin labeled radial glial fibers were disrupted in the LXRβ knockout mice both at E18.5d and P2.Conclusion LXRβ plays important role in the cell proliferation and formation of the fibers of radial glial cells in the DG of perinatal hippocampus.

关 键 词：肝脏X受体β 放射状胶质细胞 海马 发育 

分 类 号：R329.28[医药卫生—人体解剖和组织胚胎学] R338.26[医药卫生—基础医学]