摘要
本文对大鼠出生前、后的大脑皮质神经元发育进行了光镜和电镜的研究。妊娠11天胚胎(E_(11))端脑泡由充满游离的单个或多聚核蛋白体的神经上皮细胞组成。其呈放射状紧密排列,近神经管腔处有分裂细胞存在。E_(15)时,脑泡壁细胞排列出现四层结构。在E_(19)尤其明显,从内向外为室管膜层、套层、皮质板和边缘层。除室管膜层外,均存有分化不一的迁移细胞。核染色质由分布不均的细颗粒组成,核质密度低,含1—2个核仁,胞质含大量多聚核蛋白体。可见粗面内质网、线粒体、少数光面小泡。出现轴突而树突正在形成。出生后5天(P_(5)),皮质内未成熟神经元胞质内粗面内质网池增多,偶见3—4行排列。细胞开始散开,突触正在形成。从P_(12)到P_(19),神经元逐渐成熟。核染色质很细,核质电子密度低,大多含一个核仁。细胞质内见成行排列的粗面内质网,多个发达的高尔基复合体,丰富的多聚核蛋白体及微管、神经微丝、膜下囊等。并见多个轴体突触。细胞之间被神经毡充满。P_(34)到P_(51),神经元发育更完善。本文提示在神经元发育的不同阶段,细胞的不同组合排列和细胞核、核蛋白体、粗面内质网、高尔基复合体和神经突起等的超微结构变化,在作为细胞分化、成熟的标志中,均有特殊意义。此外,对形态结构的变化与功能关系进行了讨论。
The differentiation and maturation of the neurons of rat cerebral cortex in the period from embryonic day 11(E-11),15,19 to postnatal day 5(P-5),12,19,34,51 was studied by light and electron microscopy.The E-11 telencephalic wall was composed primarily of neuroepithelial cells with high electron density.Close to neurocoele,many germinal cells were in mitotic division.At E-15,four layered structures began to appear.At E-19,four layers were clear:the ventricular layer,the mantle layer,the cortical plate,the marginal layer.Except the ventricular layer,there were various migrating differentiating cells with low electron density,one or two large nucleoli were present in the nucleus,the cytoplasm contained many free ribosomal clusters,some GER,and a few axons could be seen in the extracellular space.At P-5,the GER was increased in amount aad three or four cisternae were arranged in parallel arrays occasionally in the cytoplasrrr of the immature neurons.At P-12 to P-19,the cells gradually matured.The nucleus contained fine homogeneous dispersed chromatin and,mostly,a single nucleolus.The perikaryon had several stacks of GER,a few well deyeloped Golgi cgmplexes,polysomes,microtubules,neurofilaments,etc.There were several axo-somatic synapses observed.The neuropil was well developed.At P-34 to P-51,the neurons developed more completly.The results indicated that during the different stages of development,the different cytoarchitectural features and the ultrastructural changes have special significance in signifying stages,of neuronal differentiation and maturation.The functional significance of some structural changes in the cells was discussed.
作者
唐一鹏
Tang Yipeng(Central Laboratory,Beijing College of Traditional Chinese Medicine)
出处
《神经解剖学杂志》
CAS
1987年第1期79-84,142,共7页
Chinese Journal of Neuroanatomy
关键词
神经上皮细胞
染色质
分化
粗面内质网
核蛋白体
neuroepithelial
cell
differentiation
chromatin
granular endoplasmic reticulum(GER)
ribosome.
