摘要
中华大蟾蜍胚胎在尾茅期孵化,其孵化腺细胞(HGC)是从神经管期的表皮外胚层中分化的,呈大瓶状,主要分布于头的前额部和背中线,少量分布于躯干部的背中线。电镜观察表明,神经管期 HGC 通常是几个相连一起,游离面有许多微绒毛,细胞内顶区有大量分泌颗粒,次顶区有许多色素颗粒、粗面内质网和高尔基体;分泌颗粒是由粗面内质网合成,高尔基体浓缩加工而成。随孵化酶的分泌,HGC 表面逐渐缩小,而微绒毛增长和增密。直至变态前退化的 HGC 尚未完全消失。
The embryo of Bufo bufo gargarizans hatched at the tailbud stage(st.
17).During the hatching process,the head of the embryo sticked out
first from the fertilization envelope,and the whole embryo followed.
Light microscopic examination showed that at the tailbud stage,the
large,flask-shaped epidermal cells,designated as the hatching gland.
cells(HGC),were mostly distributed over the frontal region,and a small
number of them were located along the dorsal midline of the embryo.
Transmission electron microscopic examination skowed that the HGC of
the embryo at the st.17 was characterized by the presence of many mi-
crovilli on the apical surface,a number of apically localized,membrane-
limited secretory granules,well-developed Golgi complexes and an abund-
ance of nough-surface endoplasmic reticula.There were a lot of soc-
retory granules in HGC until the muscular response stage(at.18).Scanning
electron microscopic examination revealed thad the first sign of the HGC
differentiation was the appearance of microvilli on the free surface of
epidermal cells at the neural tube stage(st.16).The free surface area
of HGC decreased and microvilli became more and longer at the st.17,
than that at the st.16.After hatching,the HGC farther decroased their
free surface area.
出处
《山东大学学报(理学版)》
CAS
CSCD
1989年第4期106-116,共11页
Journal of Shandong University(Natural Science)
关键词
中华大蟾蜍
胚胎孵化
孵化腺细胞
胚胎表皮外胚层
bufo bufo gargarizans
hatching gland cell
hatching of embryo
epidermal ectoderm of embryo