出生后大鼠海马结构的发育

目的：定量观察出生后大鼠海结构锥体细胞层和颗粒细胞层的发育。方法：用体视学原理定量分析。结果：阿蒙角锥体层，尤其是ＣＡ１区，其细胞层数逐渐减少。数密度、面数密度和体密度逐渐下降，平均体积逐渐增大。齿状回内臂逐渐延长，至Ｐ１４天接近成年水平。内外臂的细胞层数逐渐增加，至Ｐ９０天仍有增加趋势。在ＣＡ１、ＣＡ３、ＣＡ４区的锥体层和齿状回颗粒层中，数密度，面数密度和体密度按大小排序为：颗粒层〉ＣＡ１〉ＣＡ

Development of the Hippocampal Formation in the Postnatal Rats

With Nissl stain and stereological method, hippocampal formation of nine groups of postnatal rat, aged from P1 to P90 days, were studied quantitatively. The results were as following: The thickness of the Ammonic pyramidal layer, especially the CA1 sub field, was gradually thinning during the postnatal days. The numerical density, the numerical density on area and the volume density of the pyramidal cells were gradually decreased, but their mean volume grew gradually. There was a conspicuous increase in the depth and longth of the granular layer of the internal dentate limb after birth, so did the external dentate limb. Because the dentate gyrus was also expanding in the postnatal life, the increased cell-depth of the granular layer of 2 dentate limbs implied a great increase in granular cells population, though the changes of every stereological parameter of granular cells was not obvious. In the pyramidal layer of the CA1, CA3, CA4 subfields of the'Ammon's horn and the granular layer of the dentate gyms, the stereological parameter of their cells ranged from maximum to minimum as the following: the numerical density(on area ) and the volume desity were graular layer>CA1 >CA3>CA4, and the mean volume was CA3>CA4>CA1>granular layer.