人胎视网膜细胞凋亡与小白蛋白免疫阳性神经元的发育

目的：观察人胎视网膜细胞凋亡与小白蛋白Parvalbumin,PV)免疫阳性神经元的分布与发育。方法：不同孕龄的人胎16例，TUNEL法标记凋亡细胞，ABC免疫细胞化学方法观察PV免疫阳性神经元的发育。结果：（1）细胞凋亡观察：12周人胎视网膜未见凋亡细胞；15周、17周凋亡细胞较多，大小不一，分布于视网膜的全局；20周凋亡细胞主要集中在内核层，数量减少；28周凋亡细胞仅见于内核层，呈指环样外观，着色较深，数量较20周减少明显。（2）PV免疫阳性神经元发育：12周人胎视网膜未见PV免疫阳性神经元；15周、17周视网膜节细胞层和内核层有弱阳性的PV免疫阳性神经元的分布与20周相似，但内核层的数量减少，呈整齐的带状排列，着色增强。结论：在胚胎28周视网膜神经元之间的突触联系已基本建立，而PV免疫阳性神经元发育和细胞凋亡在时间和数量变化上的一致性提示Ca^2 在视网膜的发育中起重要作用。

APOPTOSIS AND DEVELOPMENT OF PARVALBUMIN IMMUNOPOSITIVE NEURONS IN FETAL HUMAN RETINA

Objective: To observe the apoptosis of parvalbumin immunopositive neurons in the developing human retina. Methods: Sixteen human fetal retinas of gestation ages 12 w, 15 w, 17 w, 20 w and 28 w were used for detection of apoptotic cells and localization of parvalbumin immunopositive neurons by using TUNEL method and ABC immunocytochemical technique. Results: (1) Apoptosis: Apoptotic cells were present in all stages but 12 w. At 15 w and 17 w the number of apoptotic cells were abundant in all layers of retina; At 20 w apoptotic cells were mainly present in inner nuclear layer; At 28 w aoptotic cells were only present in inner nuclear layer. However, when the age of fetal retina increased, the number of apoptotic cells decreased significantly compared with at 20w. (2) Parvalbumin immunopositive neurons: At 12w no parvalbumin immunopositie neurons in human fetal retina; At 15 w and 17 w it was present in ganglion cell layer and inner nuclear layer; At 20 w mainly localized in inner nuclear layer and outer nuclear layer, and the number were larger in inner nuclear layer; At 28 w was similar to at 20 w, but the number in inner nuclear layer decreased, which aranged tidily as a line. Conclusion: Synaptic junction among neurons in human fetal retina at 28w had been finished basically ,but the coherence of the time and number of parvalbumin immunopositive neurons and the apoptotic cells suggest that Ca 2+ play an important role in the development of human retina.