小鼠前庭器官的形态发生

Morphogenesis of Vestibular Organ in the Mice

目的了解小鼠前庭器官发育的形态学特征及演变规律。方法利用光镜、扫描电镜、透射电镜观察C57BL/6小鼠从胚胎第8天到刚出生期间前庭器官发育过程中的形态变化。结果C57BL/6小鼠的前庭器官在胚胎第10.5天开始发育,胚胎第11.5天形成上、后半规管始基,到胚胎第12天水平半规管始基才逐渐形成,椭圆囊已出现许多原始的感觉纤毛,而到胚胎第13天,球囊才开始发育;到胚胎第15天,椭圆囊、球囊、壶腹嵴初具成熟形态,毛细胞和支持细胞也初具雏形,到出生时,前庭器官已基本发育成熟。结论C57BL/6小鼠前庭感觉细胞在胚胎第12天开始分化,感觉上皮的形态从胚胎第12天至第18天变化最明显。椭圆囊、壶腹嵴的发生较早,随后才形成球囊,到出生时前庭感觉器官已基本发育成熟。

Objective To observe the morphogenesis and the regularity of developing vestibular organ in mice. Methods The developing vestibular organ of the C57BL/6 mice,aged from eighth embryonic day （ES） to just natal mice （PO）, was observed by light microscope, scanning electron microscope and transmission electron microscope. Results Primordial vestibule of the C57BL/6 mice arose at E10.5. Anterior and posterior semicircular canal began to form at E11.5. The lateral canal formed about one day later than the anterior and posterior canals. Primordial sensory cilia arose in utricle at E12. The saccule began to form at E13. The shapes of utricle, saccule and crista ampullaris tended to mature at E15, and the shapes of supporting and hair cells also tended to mature. The vestibular organ was mature at PO. Conclusion The sensory cells in C57BL/6 mice begin to differentiate after E12, and significant morphologic changes occurre from E12 to E18 in the developing vestibular sensory epithelia. The utricle and crista ampullaris develop earlier than the saccule. The vestibular sensory organ become fully mature at birth.