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目的：观察人胎视网膜各种神经元凋亡的发生时间，神经元凋亡与增殖、分化的关系。方法：收集８～３８周（受精龄）胎儿视网膜２７例、成人视网膜３例；核苷酸末端转移酶介导的ｄＵＴＰ缺口翻译法（ＴｄＴ－ｍｅｄｉａｔｅｄｄＵＴＰｎｉｃｋｅｎｄｌａｂｅｌｉｎｇｍｅｔｈｏｄ，ＴＵＮＥＬ法）标记凋亡细胞，光镜观察。结果：标记的凋亡细胞具有环形核、核浓缩或新月形等典型形态学特征，可见凋亡小体。胎儿视网膜神经上皮细胞、节细胞和视细胞凋亡分别发生在第８～１８周、第１２～２１周和第１４～２１周。双极神经元和Ｍüｌｅｒ细胞从第１４周持续到２７周。２８周以后胎儿及成人视网膜无神经元凋亡。结论：胎儿视网膜处于增殖状态的神经上皮细胞和刚分化出的各种神经元皆有部分进入凋亡。已分化神经元凋亡发生的时间同它们与靶细胞建立突触的时间一致。
OBJECTIVE: To observe the timing of apoptosis of various neurons in human fetal retina, the relationship between neuronal apoptosis and proliferation and differentiation. Methods: Fetal retina was collected from 8 to 38 weeks (fertilization age) in 27 cases and in adult retina in 3 cases. Apoptotic cells were labeled by nucleotide dnTP nick-end labeling (TUNEL) . Results: Apoptotic cells showed typical morphological features such as nucleus, nucleus or crescent, and apoptotic bodies. Fetal retinal neuroepithelial cells, ganglion cells and optic neuropathies occurred at weeks 8-18, 12-21, and 14-21 respectively. Bipolar neurons and Müler cells last from week 14 to week 27. Fetal and adult retinal neurons apoptosis after 28 weeks. CONCLUSIONS: Neuronal epithelial cells in the proliferating state of the fetal retina and some neurons that have just differentiated into apoptosis. Differentiated neuronal apoptosis occurs at the same time that they establish synapses with target cells.