摘要
利用光学显微镜和扫描电镜观察了河川沙塘鳢Odontobutis potamophila(Gnther)孵化腺的发生及孵化酶的分泌过程。河川沙塘鳢的孵化腺为单层细胞腺体,发生于外胚层。孵化腺(Hatching gland,HG)最早发生自眼晶体形成期的胚胎,初发生时孵化腺细胞(Hatching gland cells,HGCs)分布于头部腹面及其与卵黄囊连接处。随着胚胎的发育,HG仍以单层细胞分布于胚体和卵黄囊的外表面,HGCs数量急剧增多,细胞体积增大,分布范围更加广泛。至眼黑色素出现期的胚胎,HGCs的数量达到大约900-1200个,广泛分布于胚胎头部两侧、头部腹面及其与卵黄囊连接处、卵黄囊的前腹面。HGCs大多呈椭圆形,短径为5-8μm,长径为7-12μm,在HE染色中呈粉红色。至孵化前期时,孵化酶颗粒自HGCs顶部的开口分泌出来,分泌颗粒呈圆球形,直径为0.5-1.0μm,有的以单体的形式存在,有的粘结成团。孵化酶进入卵周液,对卵膜内层进行消化和降解,使胚胎破膜而出。孵化后2d,HGCs便从表皮中消失。
The development of the hatching gland and the secretion of hatching enzyme in Odontobutis potamophila （Gunther） were examined with microscopy and scanning electron microscopy （SEM）. The hatching gland with monolayered cells originates from the ectoderm. The hatching gland （HG） appeared first at the stage of lens formation; the hatching gland cells （HGCs） were located in the ventral part of the head and in the joint region between the head and the yolk sac. The HG with monolayered cells was still distributed on the outer surface of embryonic body and yolk sac, the number and the volume of HGCs increased significantly, HGCs spread more widely with the development of the embryo. When the embryo reached the eye pigmentation stage, the number of HGCs reached about 900 - 1 200. HGCs were located in the lateral parts and the ventral part of the head, the joint region between the head and the yolk sac, the anterior part and the ventral part of the yolk sac. The HGCs in Odontobutis potamophila （Gunther） were oval cells 5 - 8 μm in short diameter and 7 - 12 μm in long diameter. HGCs were darkish pink when stained with eosin. The hatching enzyme was formed in the HGCs at the stage of lens formation and accumulated until the prehatching stage. When the embryo reached the prehatching stage, the hatching enzyme granules were secreted into the perivitelline space from the top of HGCs. Secretory granules were spherical and 0.5 - 1.0 μm in diameter. The hatching enzyme was dissolved in the perivitelline fluid, where it gained access to the egg envelope and digested the inner layer of the egg envelope. The outer layer remained like a fragile veil that was then broken by the embryo. HGCs disappeared from epidermis about 2 days after hatching [Acta Zoologica Sinica 53 （3） ： 511 - 518, 2007].
出处
《动物学报》
SCIE
CAS
CSCD
北大核心
2007年第3期511-518,共8页
ACTA ZOOLOGICA SINICA
基金
上海市科学技术委员会重大项目(No.04DZ19301)
重庆市动物生物学重点实验室项目(No.0402)~~
关键词
河川沙塘鳢
孵化腺
发生
孵化酶
分泌
Odontobutis potamophila （Gunther）, Hatching gland, Development, Hatching enzyme, Secretion
