| Chinese giant salamander(Andrias Davidianus) is the largest and the most ancient amphibian. It is included in the critically endangered animals of IUCN red list of threatened species, since the wild population is extremely rare. Therefore, the research of Chinese giant salamander in cell biology is of great significance for the protection and development. Telocytes(TCs) are a kind of recent discovery interstitial cell associated with tissue regeneration. To date, they have been identified in interstitial tissues of various animals, but it has not been reported in the amphibian skin.In this exprement, the general morphology and ultrastructure of the skin of Chinese giant salamander were studied by using histological, histochemical and transmission electron microscopical(TEM) methods respectiverly. The results showed that, the skin was consisted of epidermis, dermis and hypodermic layer. The epidermis was composed of stratum corneum, stratum granulosum and stratum germinativum. There were melanocytes and abundant capillaries in the epidermis. The dermis was thicker than the epidermis and was made of stratum spongiosum and stratum compactum. The stratum spongiosum contained a large number of massive and thick melanin, microvessels, mucous glands and granular glands in stratum spongiosum, and the mucous glands were more plentiful than granular glands. The various components of its skin were different instructure and thickness in different parts. In addition, TCs were present in the skin by the TEM observation. TCs had special morphological characteristics, which were telopodes(TP)showing a moniliform aspect and including podoms and podomers. TCs had rich mitochondria. TCs contacted each other through TP of the same type, but also contacted with other cells. Immunohistochemical results showed vimentin, c-Kit, CD34 and PDGFRα positive cells mainly located in the stratum compactum, and the process of positive cells was elongated and bent. But those positive cells of different markers showed different positions and numbers of TCs.TEM and immunohistochemical results showed that morphology, ultrastructure and immune phenotype of TCs in skin were consistent with TCs standara. In summary, TCs distributed and existed in the skin of Chinese giant salamander, which provided new ideas for study of amphibian tissue regeneration mechanism and the treatment of Chinese giant salamander skin related diseases. |
