大鼠黑质发育的形态学研究

The morphological research on the developing rat substantia nigra

目的 观察发育过程中大鼠黑质的形态学变化。方法 对不同胎龄(embryonicday ,E ,E13、E16、E18、E2 0 )、新生(P0 )和成年大鼠中脑(黑质)区段冠状连续石蜡切片行Nissl染色,光镜观察。结果 在E13天时,中脑腹外侧出现两种极性不同的细胞,但不能区分出黑质。在E16天时可观察到黑质,此时黑质腹侧细胞较背侧细胞密集。在E18天时,黑质内部构筑发生变化,通过细胞的不同排列方式可区分黑质致密部、网状部和外侧部,细胞形态开始趋于成熟。到新生当天时,可观察到黑质网状部的细胞较胚胎时稀疏,黑质致密部的细胞开始密集,细胞呈现成熟神经元的形态。结论 在大鼠出生之前,其黑质内部构筑的演变已趋成熟。

Objective To observe the morphological changes of the substantia nigra during the development of fetal rat.Methods Continuous coronal sections were prepared from perinatal and adult rat midbrains embedded in paraffin. Nissl staining method was used before the sections were studied by microscopy.Results Two sorts of cells with different polarities were observed in rat midbrain on E13,while the profile of the substantia nigra remained not to be delineated. By the day of E16, the profile of the substantia nigra became evident, with the cells in the ventral part being denser than in the dorsal part. The cytoarchtecture of the substantia nigra changed on E18, and the shape of the cells became mature. According to the distribution and arrangement of the cells, the substantia nigra of this time could be divided into three parts. On birth, the density of the cells in the pars reticulata of the substantia nigra descreased, while that in the pars compacta increased. The shape of the cells appeared mature.Conclusion The maturation of the internal construction of rat substantia nigra is accomplished by birth.