RESUMO
The testicular organization and semicystic spermatogenesis of Scorpaena porcus and Scorpaena scrofa are analyzed by means of optic and electron microscopy and immunohistochemical techniques. The testicular structure of S. porcus and S. scrofa belongs to the unrestricted spermatogonial type, but has typical features of the restricted type. Moreover, the structure presents an epithelioid arrangement of Sertoli and germ cells rather than the germinal epithelium that appears in the majority of teleosts. After the cysts open, Sertoli cells hypertrophy and remain on the basement membrane, linked by interdigitations and tight junctions and bordering the lumen of the lobule, which at this moment works as an efferent duct. Secretions of Sertoli cells usually function in the nutrition of germ cells, and they seem to contribute in it even in this kind of spermatogenesis in which the free lumen spermatids do not have any connection with Sertoli cells. In addition, Sertoli cells can divide after the cysts have broken apart and hypertrophied, suggesting that they are still important for the final maturation of spermatozoa and seminal fluid formation.
