| Abstract: | Background: There is little information about the distrib ution of cytoskeletal components in the testes of teleost fish. The aim of this (tublin, actin, vimentin, desmin, and cytokeratins) in the sertoli cells of Gambusia affinis holbrooki and in their efferent duct epithelial cells which are possibly orginated from the Sertoli cells Methods: Light and electron microscopic immunocytochemical studies and Western blotting analysis were performed in G. affinis testis. Results: Actin immuncor eaction was observed in the Sertoli cells at all spermatogenic stages, although the intensity of the reaction varied from one state to another. Sertoli cells that support supermatogonia or supermatocytes showd a weak immunoreaction which was uniformly distributed throughout the cytoplasm and somewhat more concentrated at the level of the inter-Sertoli specialized junctions, Immunoreaction to actin increased during the first states of supermiogenesis and was manly localized beneath the plasma membrane. This immunoreacction was more intense in the basal than in the aical ctoplasm of Sertoli cells. In a more advanced stage of supermiogenesis, actin immunoreaction become stroger in the apical cytoplasm where Sertoli cells displayed cytoplasmic projections around each supermatid. After sperm release, the apical Sertoli cell cytoplasm still showed an intense actin immunoreaction. Intense immuncreation to actin was also observed in the epithelial cells lining the efferent ducts. Immunoreaction to tubulin was diffuse throughout the Sertoli cell cytoplasm. No immunocreation to vimentin or desmn was observed in the Sertoli cells during the spermatogenic process. Immunoreation to both vimentin and desmin was observed in the efferent ducts cells. Desmin immunoreaction was also observed in the seminiferous tubule boundary cells, mainl in the sections showing germ cell cysts at the last stages of spermiogenesis and in the peritubular cells that surrounded the efferent duct epitheium. Immunoreaction to cytokeratins was found in the endothelium of testicular blood vessels but not in the Sertoli cells or in the efferent duct epithelium. Conclusions: Immunoreaction pattern to cytoskeletal proteins in the Sertoli cells of G. afinis: differs from that reported in mammalian Sertoli cells. These differences include the distribution of action filaments and the absence of dectectable vimentin immunoreaction in G. affinis: Sertoli cells. © 1995 Wiley-Liss, Inc. |
