中文摘要：

目的探讨细胞外信号调节激酶（ERK）信号转导通路在海马提取液诱导神经干细胞向神经元分化过程中的作用。方法切割12只sD大鼠右侧穹隆海马伞，14d后分别取切割侧和正常侧海马制成匀浆，离心收集上清液，蛋白定量后备用。将获取的鼠胚海马源性神经干细胞培养在24孔板中，分成3组，每组8孔，于无血清条件下，切割组加切割侧海马提取液；正常组加正常侧海马提取液；对照组不加上述海马提取液。培养14d后进行微管相关蛋白2（MAP．2）与p-ERK的免疫荧光双标检测。结果MAP．2阳性神经元数量、胞体面积和细胞周长在切割组、正常组和对照组中依次减少，3组之间均有显著性差异。MAP．2、p-ERK免疫荧光双标细胞数量在切割组、正常组、对照组中也依次下降，但双标记细胞数占MAP一2阳性神经元数的百分比却反而依次增加，两者3组之间均有显著性差异，双标细胞大多为欠成熟细胞。结论切割穹隆海马伞侧海马提取液较正常海马提取液有明显促使神经干细胞向成熟神经元分化的作用；形态学初步证实ERK信号转导通路可能与神经干细胞向神经元分化有关。

英文摘要：

Objective To investigate the effect of extracellular sigual-regulated kinases （ERK） signal transduction in the process of NSCs differentiating into neurons in the fimbria-transected hippocampi＇ s extracts. Methods Twelve Sprague-Dawley rats＇ right fimbrias were transected. The extracts were gained from the fimbria-transected hippocampi at the 14th day normal rat, and the extracts supernatant fluid was collected after centrifugal process, then the protein concentration in the extracts was determined. In the serum-free medium, NSCs from the fetal hippocampus were planted on 24 well culture plate, then were divided into three group and eight wells for each group as follows： the transected group contained the extracts of the fimbria-transected hippocampi; the normal group contained the extracts of the normal hippocampi; the pure control group have no extracts. After cultured for 14 days, the cells were detected by using MAP-2 and p-ERK immunoflnorescence. Result The number, area, perimeter of MAP-2 positive neurons were all declined in transected group, the normal group and the control group orderly. Statistic results showed significant difference between every two groups. The number of MAP-2/p-ERK double-positive neurons were decreased in transected group, the normal group and the control group orderly, but the percentage of double-labeled neurons in total MAP-2 positive neurons were increased in turn. In these two aspect, there were also significant difference between every two group. And most of the MAP-2/p-ERK double-positive neurons were immature. Conclusion The extracts of the fimbriatransected hippocampi had obvious effects on promoting NSCs differentiating into neurons and speeding up the maturation of neurons than those of the normal hippocampi. The morphological results showed that ERK signal transduction might be related to the differentiation of NSCs into neurons.