摘要
扬子鳄内耳的椭圆囊与球囊间以及前、后半规管形成的总脚处均存在瓣膜，半规管、壶腹嵴及囊斑的组织结构与其他爬行类动物相似。扬于鳄耳蜗伸长且弯曲，由典型的三个腔即前庭阶、鼓阶和中阶（膜蜗管）构成；基膜中间厚、两侧薄，在耳蜗腹端较宽，向背端逐渐变窄；柯蒂氏器由支持细胞和两型毛细胞（高毛细胞和矮毛细胞）组成；前庭膜厚且高度血管化。在平均约２８℃孵化温度下，孵化后第２天胚胎耳板凹陷呈浅杯状；第６天凹陷口封闭形成耳泡；第１０天出现球囊与椭圆囊部的分化，椭圆囊部出现前、后、侧壶腹原基；三个半规管在第１０—２０天中形成。第１４天原始膜蜗管出现；第１８天原始膜蜗管内侧壁局部区域细胞层增厚；第２０天膜蜗管大大延长并弯曲；第３０天前、后壶腹嵴基本发育成形；预定柯蒂氏器出现了柱状或瓶状毛细胞的分化。
There is valve either locating at the place between the utricle and saccule,and at the crus commune formed by anterior and posterior semicircular canals of the inner ear in Alligator sinensis. The histological structure of semicircular canals,cristae and maculae was shown similar to that of other reptiles. The cochlea was elongated and curved. It contained three typical cavities: scala vestibuli, scala tympani and scala media (cochlear duct). The centrally thickened basilar membrane was wider at the ventral of cochlea and tapered toward its dorsal extremity. The basilar papilla was formed by two types of hair cells(tall and short)and supporting cells. The vestibular membrane was shown thick and highly vascularized. At a mean temperature(around 28℃ ), the otic placodes invaginated like a shallow cup at 2nd day of incubation,and the otic vesicle was shut up from ectoderm at the 6th day of incubation. At the 10th day of incubation,the presumptive utricle projected to produce presumptive saccule and primordia of anterior, posterior and lateral ampulla. Three semicircular canals were formed during the period of 10-20th days of incubation. The primitive cochlear duct,appeared at the 14th day of incubation,thickened regionally along its.inner wall at the 18th day of incubation,elongated greatly and curved at the 20th day of incubation. At the 30th day of incubation,the anterior and posterior cristae had basically been formed,and the differentiation of pillar or bottle-shaped hair cells started on the presumptive basilar papilla.
出处
《动物学报》
SCIE
CAS
CSCD
1994年第1期75-81,共7页
ACTA ZOOLOGICA SINICA
基金
国家自然科学基金资助课题
批准编号850323
关键词
扬子鳄
内耳
组织结构
胚胎
发育
Alligator sinensis, Inner ear, Histological structure, Early embryonic development
