花背蟾蜍蝌蚪皮肤的结构与发育

为研究花背蟾蜍(Bufo raddei)蝌蚪在变态发育期皮肤的显微结构特点,选取G19、G22、G26、G36、G41、G43和G46共7个发育期蝌蚪的连续石蜡切片及成体的背部皮肤切片,采用H.E和AB-PAS染色方法,观察了皮肤各层结构的发育时序并进行了相应的测量.结果表明,在G19、G22和G26蝌蚪表皮均为1层细胞；G36蝌蚪皮肤细胞形态和层数在背腹部出现了显著的区别；在G41基本完成了表皮2层细胞的构建；G43期完成完整的真皮构建,其中分布有毛细血管和2种皮肤腺.G46皮肤在厚度、腺体和毛细血管分布等方面表现出了明显的区域性差异,并与成体皮肤结构有明显的差别,显示出蝌蚪在发育过程中皮肤结构的变化与其生存环境之间紧密的关联性.

The Structure and Development of Larval Skin in Bufo raddei

In order to reveal the skin microstructure characteristics during metamorphosis of Bufo raddei tadpoles,we observed the continuous paraffin sections of skin from seven developmental stages of the tadpoles (including stages 19,22,26,36,41,43 and 46) and the dorsal skin paraffin sections of the adult toad. The structural development timing of different skin layers was observed by H.E staining and AB-PAS methods. The results showed that one layer of cells existed at stage 19, stage 22 and stage 26 skin epidermis, and the cell morphology and the number of layers between the dorsal skin and the belly skin showed significant difference at stage 36. The structure of cells in two layers of the skin epidermis was basically completed at stage 41, and the dermis structure was completed at stage 43, in which the micro-vessels (capillaries) and two types of the skin glands could be observed. The skin thickness and numbers of glands and micro-vessels showed significant difference in different regions at stage 46, and were significantly different from the skin structure of the adult toad. The results indicated a close correlation between the development of the tadpole skin structure and its living environment.