非洲爪蟾眼的形态发生研究

Eye Morphogenesis in Xenopus laevis

详细观察和描述了非洲爪蟾Xenopus laevis眼的发生和发育变化过程,并分别对各发育时期视网膜的厚度进行了定量分析。非洲爪蟾眼的发生开始于眼原基的形成,进而形成视泡;晶状体的发生是在视杯外壁增厚的同时诱导覆盖其上的胚胎外胚层内层增厚,形成预定晶状体板;在视网膜和晶状体共同诱导下,预定角膜上皮变为透明的角膜。在视杯出现之前,预定RPE的厚度由厚变薄,NR层不断地增厚直至结构功能完善。

Eye morphogenesis in the Xenopus laevis was observed and described in detail. The attention was paid mainly to retina, lens and cornea development. The results indicated that eye morphogenesis in the Xenopus laevis began with the formation of optic primordium and soon it formed optic vesicle, which started with parietal margin apophysis of diencephalon, and ventriculus opticus extended encephalocoele to form a larger eavum. Lens morphogenesis induced the building up of inner ectoderm of the emblyo to form prospective lens placode, during which the exine of optic cup thickened. Prospective lens placode continued to thicken to ataetie circle with invagination of exinc of optic cup, then deviated with ectoderm and invaginated. Prospective corneal epithelium secreted extracellular matrix to internal surface and generated primary corneal stroma, which was induced by retina and lens. Then interstitial cells invaded in primary corneal stroma and led to the formation of secondary corneal stroma and corneal endothelium finally became transparent corneal cornea.