鸡和大鼠小脑发育的比较观察

观察发育阶段不同的鸡和大鼠的小脑标本外形,并在光学显微镜和电子显微镜下观察了结构。鸡卵在孵育的第6天,小脑原基出现。第15天小脑皮质形成,普肯野氏细胞(普氏细胞)排成一层。新生鸡小脑皮质发育近成年状态,普氏细胞发育基本完成。大鼠在生后第5天小脑皮质形成,第20天发育成熟。在生后第5天普氏细胞排成一层,第20天接近成熟状态,此时在电子显微镜下显示为粗面内质网和多聚核蛋白体区域性集中分布。鸡小脑比大鼠小脑发育早,这是种属差异。

DEVELOPMENT OF CEREBELLUM OF CHICK AND RAT

The configurations and histological structure of cerebellumof chick and rat at different stage of development were observed withlight and electron microscopes respectively.The results are as follows:the cerebeIlar cortex of the chick forms at day 15 of embryo(E15)and matures at day E21.It is also at day E15 that Purkinje cellsarrange in 1 layer.The mature Purkinje cells can be seen at new bornperiod microscopically.But in rat the cerebellar cortex forms at day 5after birth and matures at day 20.At day 5 Purkinje cells arrange in 1layer and become mature at day 20.Under electron microscope,the roughendoplasmic reticulum,accompanied by polyribosomes,is distributedregionally in Purkinje cells of both chick and rat at mature stage ofdevelopment.It is shown by this study that the development of the cerebellum ofthe chick is earlier than that of the rat owing to race differences.