摘要：本研究用HE染色和超薄切片技术，对4～8月胎儿小脑皮质神经细胞的发育和细胞构筑进行了观察。结果发现从胚胎4月开始，小脑已由两侧的小脑半球和蚓部组成，可见皮质和髓质。皮质分为外颗粒层、分子层、中间层、内颗粒层四层。随月龄增加，外颗粒层的相对厚度下降，绝对厚度增加。8月时，皮质可分为外颗粒层，分子层，蒲肯野细胞层和内颗粒层。电镜观察发现4月胎儿小脑皮质的神经细胞排列紧密，细胞核大而圆，突起少，此时突触处于形成期，突触前膜、突触后膜和突触间隙已清晰可辨，但突触小泡很少。6月时，神经细胞增大，胞质中细胞器的种类和数目较4月时有明显的增多。绝大多数突触依然是突触样连结，特点是两膜呈对称性增厚，突触间隙清晰可见，突触前终末内线粒体结构较幼稚，突触小泡数目较少。8月时的神经元发育基本成熟，细胞突起的数目增多且较长。突触结构趋于成熟，突触前后膜增厚，突触前终末内的小泡增多，且向前膜聚集，突触样连结数目减少，典型突触增多。以上这些结果表明，小脑皮质的神经细胞随胎龄增加，其结构和功能逐步完善，7～8月间是发育的重要时期。

The Development of Neurons of Cerebeilar Cortex in Human Fetus

qian Xuesong(Department of Anatomy, Medical University, Shijiazhuang 050017)

li Chenli(The First People Hospital of Shijiazhuang)

tong Yuhong(Department of Anatomy, Medical University, Shijiazhuang 050017)

Abstract：In this study, using HE staining and ultrathin section technique, we studied the development of cerebellar cortex neurons of the 4-8 months human fetus. The results showed that the cerebellum was divided into hemisphere and vermis at April of embrya. The cortex included the external granular layer, the molecular, the middle and the internal granular layers. At August of embyo, the cortex included the external granular layer, the molecular, the Purkinje cell and the internal granular layers. The ultrastructure of the cortex cells in the period of the April to August of embyo were described in detail.

Keywords：cerebellum; human fetus; development参考文献：

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