Differentiation of Purkinje cells and their relationship to other components of developing cerebellar cortex in man
Differentiation of Purkinje cells and their relationship to other components of developing cerebellar cortex in man
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浦肯野细胞的分化及其与人类小脑皮质发育中其他成分的关系
DOI：
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发表时间：
1976
期刊：
影响因子：
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通讯作者：
P. Rakić
中科院分区：
文献类型：
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作者：
N. Zečević;P. Rakić
通过Golg浸渍法和电子显微镜在不同出生前和出生后年龄的人体标本中分析浦肯野细胞的分化及其与发育中小脑皮质其他成分的关系。先前在其他物种中已经认识到的浦肯野细胞成熟的三个阶段在人类中也很明显：第一阶段主要占据胎儿的第四个月（12-16周）;第二阶段持续到第五，第六和第七个胎儿月（16-28周）;第三阶段在整个子宫内生命的剩余期间和出生后的第一年内延伸，此后以缓慢的速度继续。在第一阶段，浦肯野细胞分布在一层，几排深。它们的双极胞体是相对平滑的，只有少数突起在顶端和基底细胞极。在第二阶段的3个月期间，浦肯野细胞逐渐组织成单行。它们的体细胞被额外的随机定向的树突状突起和许多体细胞棘（伪足）所覆盖。在第二阶段开始时，浦肯野细胞的体细胞棘及其未成熟的树突轴上出现了第一个形态学上明确的突触，并在18至24周期间变得更加突出。在第三阶段，树枝状乔木变得扁平的平面横向叶和体刺消失。棘出现在第24和第28胎周之间的二级和三级树突上，并在整个第三阶段随着新的树突分支的发展而继续增加。这些观察结果表明，灵长类小脑中的细胞成熟和突触发生与非灵长类物种中的这些事件不同，在出生时间，每个阶段的相对持续时间和神经元分化所需的总时间方面。人类浦肯野细胞树突的分化时间延长和生长缓慢可能是由于颗粒细胞和浦肯野细胞之间存在着复杂的数量关系。这可能不仅仅是人类浦肯野细胞及其树突尺寸较大的反映。
The differentiation of Purkinje cells and their relationship to other components of the developing cerebellar cortex were analyzed by the Golgimpregnation method and by electron microscopy in human specimens of various pre‐ and postnatal ages. The three stages of Purkinje cell maturation that have been previously recognized in other species are also evident in man: the first stage occupies primarily the fourth fetal month (12–16 weeks); the second stage lasts through the fifth, sixth and seventh fetal months (16–28 weeks); the third stage extends throughout the remaining period of intrauterine life and the first postnatal year and continues at a slow rate thereafter. During the first stage, Purkinje cells are distributed in a layer, several rows deep. Their bipolar somas are relatively smooth and have only a few processes at the apical and basal cell poles. In the 3‐month period of the second stage, Purkinje cells become gradully organized into a single row. Their somas become invested with additional randomly oriented dendritic processes and numerous somatic spines (pseudopodia). The first morphologically well‐defined synapses appear on the Purkinje cell somatic spines and on their immature dendritic shafts at the beginning of the second stage and become more prominent during the period from 18 to 24 weeks. In the third stage, the dendritic arbor becomes flattened in the plane transverse to the folium and somatic spines disappear. Spines appear on the secondary and tertiary dendrites between the twenty‐fourth and twenty‐eighth fetal weeks and continue to increase in number during the entire third stage as new dendritic branches develop. These observations indicate that cellular maturation and synaptogenesis in the primate cerebellum differ from these events in non‐primate species, with respect to time of birth, in the relative duration of each phase and in the total time necessary for neuronal differentiation. The protracted time of differentiation and the slow growth of Purkinje cell dendrites in man may be due to the numerically complex relationships existing between granule and Purkinje cells. It is probably not simply a reflection of the larger size of human Purkinje cells and their dendrites.