Studies On Microstructure And Infrastructure Of Testis Of Little Salamander, Batrachuperus Pinchonii

Spermatogenesis is one of the most important section of developmental biology. Sex hormone is one of factors that regulate Spermatogenesis. Interstitial cell, that regulate germ cell differentiation and Spermatogenesis is the main testosterone source in the testis. The sertoli cell is the central point of exchange information and material. The relationship among the germ cell, sertoli cell and interstitial cell is the key problem in the reproductive endocrinology. The little salamander (Batrachuperus pinchonii) of urodele Amphibians can be used as medicine and food, and have some economic value. In order to reveal the developmental mechanism deeply, add documents to the reproductive biology, and lay the foundation of amphibians exploring. The microstructural and ultrastructural examination of the litter salamander testis was carried out to show the Spermatogenesis and the relationship between the sertoli cell and interstitial cell during the Spermatogenesis. The results as follows.1 The testicular structure and reproductive cycle of B. pinchonii was studied .The testes of B.pinchonii are lobular type. In April, the testes were at the stage of spermatogonic proliferation, when primary spermatogonia divided and developed into secondary spermatogonia, which and sertoli cell form spermatogenic cysts. In May, the spermatocyte was observed in testis. In June, the spermatocyte was in the first meiotic division. In July, the testis entered spermiogenesis. During this stage, germ cells in the cysts developed into sperms finally. In August, the sperms appeared in cysts. In September, the testis was filled with the mature sperms. In October, sperm in the testis began to decrease. Spermatogenesis in this species follows an annual cycle.2 In April, some special structure, which consists of columnar cells, was observed in the caudal testis. In this structure, there were some mature sperms and some material that nourish the sperms and make them go through the winter. The special structure, which can store sperm, was not reported till now,3 The sperm of the little salamander is similar to that of toad in shape, both of them had the axonema, axial fiber and undulating membrane in their tail. But there is still some significant difference between them: the juxta-axonemal fiber is close to the eighth axial microtubular in the sperm of the little salamander, while the one is closeto the third one in the toad.4 In the spermiogenesis, there were smooth endoplasmic reticulum, lipid droplet and mitochondria in sertoli cell. These characteristics revealed that the sertoli cell might have the function of secreting steroid. In the cytoplasm, there were some glycogen that nourished the spermatozoa, and some primary lysomes, residual bodies and myelin body that showed the phagocytosis function.5 In September, when the sperms were released, the sertoli cells seemed to degenerate and the interstitial cells transformed into the Leydig cell, there cells shows the ultrastructural characteristics of steroid-secreting cells: some developed endoplasmic reticulum, mitochondria with tubular cristae and lipid droplets. With the change of season, their morphology would change.6 The sertoli cell and interstitial cells not only inhibited each other, but depended on each other as well.