人胎儿第四脑室底的扫描电镜观察

SCANNING ELECTRON MICROSCOPIC OBSERVATIONS OF THE FOURTH VENTRICULAR FLOOR IN HUMAN FETUS

本文应用扫描电镜的方法观察了人胎儿第四脑室底的超微结构。结果发现第四脑室底布满大量的纤毛和微纤毛,纤毛的分布有一定的部位差异。并证实了第四脑底室存在着接触脑脊液的神经元的胞体、树突和轴突,该神经元的脑体为梭形或球形还可见到一个或两个以上的突起。室管膜上神经纤维发自神经细胞或自室腔外穿入而来。另外,在室管膜上,观察到了神经胶质样细胞和类组织细胞。神经胶质样细胞呈不规则球形,表面比较光滑,有较多的棘状突起自胞体伸出,没有轴突和树突之分,类组织细胞大多呈球形,表面有微纤毛或泡状结构,突起较少,在某些区域还可见其聚集成群。本文并对上述结构的功能进行了讨论。

The ul trastructural feature of the fourth ventricle in human fetus were examined by scanningd by scanning electron microscopy. Numerous cilia, microv il 1 i have been observed on the cerebral ven-tricule surface. The distribution of the cilia showed regional variation. The somata, dendrites and axons of the CSF-contact ing neurons existed in above mentioned rentricles. The neuronl somata were round or fusiform in shape with one or more cytoplasmic processes. The supraependymal nerve fibers came from the supraependymal neuron-like cells or neurons outside the ventricle by Penetrating into the cavity. In addition, neuroglia-like cells and hjstocyte-like cells on the ependymal surface were found. The former had a irregular globular cell body with smooth surface and many filopodia-like processes which showed no polarity. The latter had less cytoplasmic processes. The surface of these cells were studied with numerous small blebs ormicrovilli. The function-of the structures mentioned above were discussed