摘要
目的:研究并分析神经干细胞的超微结构和生物学特征。方法:无血清培养大鼠胚胎中脑组织中神经干细胞,用血清诱导分化。扫描及透射电镜观察神经球及单个神经干/祖细胞的超微结构。结果:培养的神经干/祖细胞呈神经球样生长,经血清诱导可分化为神经元样和神经胶质细胞样细胞。扫描电镜下神经球表面的细胞直径约为5～10μm,常3～5个以上彼此粘附聚集成簇,松散不规则分布。透射电镜下神经球由神经干细胞和无定形结构的物质构成,根据电子密度不同分为明细胞和暗细胞。神经球内部大部分相邻细胞排列紧密,部分细胞可见有贯通两相邻细胞膜的通道;少部分相邻细胞排列疏松,并见部分相邻细胞间有壁呈腺泡样结构的囊泡的释放活动。神经球内干/祖细胞核质比高,多种细胞器不发达,高尔基复合体、核糖体、溶酶体等在不同神经干/祖细胞中的数量和分布不一致。多见自噬小体,髓样体。大部分细胞为单核,罕见双核、肾形核,常染色质多分布均匀,异染色质少,多见单个核仁。结论:胚鼠中脑神经干/祖细胞球内紧密排列的相邻细胞间有贯通两胞膜的孔道,排列疏松的相邻细胞间有腺泡样结构的囊泡的释放活动。研究结果为进一步研究多因子对神经干/祖细胞的发育增殖、定向分化的调控及其相关途径奠定了一定基础。
Objective：To study the ultrastructural and biological characteristics of neural stem cells/progenitors（NSPCs）from rat embryo midbrain tissue.Methods：NSPCs from the midbrain of rat embryos were cultured in a serum-free media,and then were induced by serum to differentiate.The ultrastructure of NSPCs was studied through scanning or transmission electron microscope.Results：The NSPCs growed to be neurosphere-like cells after days of culture and were able to differentiate into neurons,astrocytes and oligodendrocytes in a serum-containing media.The neurospheres were studied under scanning electron microscope.It was found that cell diameters of neurosphere superficies ranged between 5-10 μm and that three or five cells were often adhered to one another and aggregated to form a cluster,yet the cell-cell junctions were not compact and ordered.The neruospheres were made up of NSPCs and nonfixiform materials were observed under transmission electron microscope,and the cells could be divided into lucent and dark ones according to their electron densities.The mmajority of the flanking cells were compactly arranged in nemospheres,and passageways penetrating adjacent plasma membranes were found between some of the cells.The minority of the flanking cells was not compactly arranged.There were acinus-like vesicles releasing material activity between some adjacent cells.High ratio of nucleus to cytoplasm was noticed in the NSPCs.Many kinds of organelles,Golgi complex for instance,and endocytoplasmic reticulum were underdeveloped,and the amounts,types,distribution of lysosome and ribosome varied in different cells.Autophagosomes quaque was also observed.Caryons were only one in most cells and many of them were globula in shape,dikaryons or kidney-shaped karyons were hardly to be observed,and with only one chromatospherite quaque in each of them.Conclusion：Tightly arranged flanking cells in neurospheres,with passageways penetrating adjacent plasma membranes,loosely arranged flanking cells,with acinus-like vesicles that have releasing activity have been found.Our finding is fundatnental in further research on the development,proliferation,orientation,and differentiation of NSPCs that are controlled by many factors.
出处
《神经解剖学杂志》
CAS
CSCD
北大核心
2010年第5期555-560,共6页
Chinese Journal of Neuroanatomy
基金
贵州省科技厅科技基金项目[(2004)3002]
贵阳市科学技术计划项目[(2004)26号]
关键词
神经干/祖细胞
神经球
分化
超微结构
大鼠胚胎
中脑
neural stem cells/progenitors
nervoussphere
uhrastructure
differentiation
rat embryo
midbrain
