仿刺参生殖腺发生与早期分化的组织学观察

Histological Observation on Genesis and Early Differentiation of Gonad in Apostichopus japonicas

采用组织学方法,初步研究了仿刺参(Apostichopus japonicus Selenka)生殖腺的发生及早期分化的过程。结果表明,仿刺参的生殖腺位于背肠系膜处,在体长为0.1 cm的稚参中出现含有约10个原生殖细胞的原始生殖腺;体长0.5cm的稚参,原始生殖腺的中央腔明显,生殖腺初具雏形;体长3 cm的幼参中,生殖腺出现二分枝并且生殖腺上皮出现分层结构,内层为排列较松散的生殖细胞,外层为排列紧密的个体较小的上皮样细胞,此时仿刺参生殖腺的基本结构已经具备;幼参体长4 cm时,生殖腺的部分管壁内层细胞向内发生褶皱,形成以生殖细胞为主的嵴状突起,随着发育的进行,生殖腺管腔内侧的嵴状突起更加密集。

The genesis and early differentiation of gonad in Apostichopus japonicas was studied using histological method. The results showed that the gonad was located at the anterior region of the dorsal mesentery. For those body length at 0. 1 cm juvenile, the original gonad contained about 10 PGCs. The primary structure of gonad was formed as the cavity was obvious in the 0. 5 cm juvenile. When the juvenile reached to the length of 3 cm, the gonad was similar to the adult in the structure, which had two bran- ches and the wall was composed of two main layers： the outer coelomic layer consists of smaller epithelial cells; the inner layer consists of loosely arranged germ cells. In 4 cm juvenile, part of the inner layer of the gonad wall folded inward to form germ cells-based ridge-like protuberances. With the development of juvenile, the ridge-like protrusions inside the lumen of gonad were more intensive.