花背蟾蜍角膜早期发育期间胎球蛋白结合位点的分布

The Distribution of Binding-sites for Fetuin in Cornea during Early Development of Bufo raddei Strauch

本文用酶标胎球蛋白作为探针，在光镜水平对花背蟾蜍角膜早期发育中胎球蛋白结合位点（ＦＢＳ）进行组化定位．结果表明ＦＢＳ主要分布在角膜上皮层：胚胎发育至２０期，ＦＢＳ开始出现；在２２期和２３期，基底细胞中ＦＢＳ减少，在基膜附近大量密集；２４期，ＦＢＳ在基底细胞中再度增加而均一分布在上皮层；表层细胞游离面在２５期出现无ＦＢＳ的区带；纤毛细胞中始终无ＦＢＳ分布，而只在２５期时其游离面出现ＦＢＳ．认为ＦＢＳ参予角膜中Ｂｏｗｍａｎ＇ｓ膜的形成和间充质细胞的附着，是导致角膜上皮层变薄透明的因素之一。

The histochemical localization of the binding-sites for fetuin (FBS)in cornea during the early development of Bufo raddei Strauch were studied by using fetuin-HRP probe.The results indicated that FBS is localized in corneal epithelium mainly. FBS appeared at stage 20. From stage 22 to 23, the FBS decreased in basal cells and concentrated in basal membrane. At stage 24, it recovered in basal cells and distributed in all epithelium uniformly. No FBS layer was found on the free surface of superficial cells at stage 25. The FBS did not present in ciliated cells, but only appeared on its free surface at stage 25. These results suggest that FBS participating in the formation of Bowman's membrane and mesenchymal cell adhesion may be one of the factors that result in transparency and thinning of corneal epithelum.