金黄地鼠上丘的生后发育进程──细胞构筑及免疫细胞化学研究

THE TIME COURSE OF POSTNATAL DEVELOPMENT OF THE SUPERIOR COLLICULUS IN GOLDEN HAMSTERS

为探讨金黄地鼠上丘的生后发育进程，用神经组织染色技术和免疫细胞化学技术通过计算机图象分析对生后不同日龄的金黄地鼠上丘的细胞构筑和突触素的表达进行了研究。结果显示：（1）上丘外灰质层神经元密度在新生时最高，随日龄的增长而显著降低，在出生到生后5d之间的阶段降低幅度最大；出生5d以后，变化趋于平缓；至生后15d，上丘外灰质层神经元密度已接近于成年动物。神经元密度的降低可能与发育过程中的自然发生的神经元死亡有关。（2）金黄地鼠上丘内突触素免疫反应阳性产物平均光密度值在从出生到成年鼠的发育阶段中呈上升趋势，但变化最为明显的时间段是生后10d到15d之间，至生后15d时，突触素免疫反应产物的平均光密度值已接近成年鼠的水平，此时间段的前后．光密度的变化都较为平缓，此结果提示，金黄地鼠上丘内突触素免疫反应产物平均光密度的升高可能与突触的形成发育加速及视觉功能的日趋成熟有关。

In order to know the time course of postnatal development of the superior colliculus in the golden hamster. The cell architecture and expression of synaptophysin in the superior colliculus have been studied with morphological, immunocytochemical and morphometrical methods in newborn hamsters in different postnatal stages. The following results were obtained:(1) Neuronal density in the outer gray layer of the superior colliculus was highest in the newborn (D0) hamster and there was a distinguishable decrease in the cell density during the first five postnatal days. After postnatal day 5, the developmental changes in the cell density became a smooth line until adult. The decreased neuronal density might be related to naturally occurring neuronal cell death in developing process of the superior colliculus. (2) The optical density of synaptophysin immunoreactive products in the superior colliculus of golden hamsters increased gradually during the whole developmental period after birth and reached nearly its maximum by the postnatal day 15. The results suggest that the increase of synaptophysin immunolabeling density in the superior colliculus of golden hamsters might be related to the setting up and developing of the synapses in the outer gray layer of the superior colliculus, and also, it reflected the natural development process of the visual function in postnatal hamsters.