Brn-4在大鼠海马神经干细胞向神经元分化中的作用

为探讨Brn-4在海马神经干细胞(neural stem cells,NSCs)向神经元分化过程中的作用,分别制备切割海马伞侧和正常侧海马提取液,将鼠胚海马神经干细胞球分成3组:(1)切割组加入含切割侧海马提取液的DMEM/F12无血清培养基;(2)正常组加入含正常侧海马提取液的DMEM/F12无血清培养基;(3)对照组加入单纯的DMEM/F12无血清培养基。培养后第14d行Brn-4/MAP-2免疫荧光双标染色。在荧光显微镜下分别计数每个视野下Brn-4单标神经元和Brn-4/MAP-2双标神经元的数量,并测量双标神经元的胞体面积、细胞周长以及Brn-4的免疫荧光强度。用图像处理系统和Stata7.0软件对所得数据进行统计学分析。结果显示:Brn-4/MAP-2双标神经元数在切割组中较多、胞体较大、突起较丰富,且Brn-4的免疫荧光亦较强;正常组次之,对照组最差。上述数据经组间比较分析,3组间差异有显著性意义(P<0.01)。本研究结果提示Brn-4在海马神经干细胞向神经元分化过程中可能发挥重要作用。

EFFECT OF Brn-4 ON THE NEURAL STEM CELLS OF THE HIPPOCAMPUS DIFFERENTIATION INTO NEURONS OF RATS

To investigate the effect of Brn-4 on the neural stem cells differentiation into neurons,the extracts from fimbria transected and intact hippocampus of adult SD rats were respectively obtained.NSCs isolated and expanded from the hippocampus of embryonic rat were divided into 3 groups as following:(1)the transection group:DMEM/F12 medium containing extract of the fimbria-transected hippocampus was added;(2)the normal group:DMEM/F12 medium containing extract of the normal hippocampus was added;(3)the control group:DMEM/F12 medium without any extract.The neurons differentiating from NSCs were stained by immunofluorescence double-labeling of Brn-4 and MAP-2 on the 14th day after culturing.The numbers of Brn-4 single-labeling neurons and Brn-4/MAP-2 double-labeling neurons per field were accounted respectively through the fluorescence microscope.And the area of cell body,perimeter and the immunofluorescence intensity of Brn-4 of the double-labeling positive neurons were also detected respectively.Image processing system and Stata7.0 statistical software were used to analyze the data.The results showed that the numbers of Brn-4/MAP-2 double-labeling neurons were bigger,the cell bodies were larger,the process was longer and immunofluorescence intensity of Brn-4 was superiorest in the transection group,then the normal group,and the control group was the last.The differences were significant between either two groups through comparison(P<0.01).It is suggested that Brn-4 may play an important role in the process of NSCs differentiating into neurons.