Histological and Stereological Evaluation of Zebrafish (Danio rerio) Spermatogenesis with an Emphasis on Spermatogonial Generations

摘要: The zebrafish has become an important vertebrate model for basic and biomedical research, including the research field of biology reproduction. However, very few morphological stereological data are available regarding testis structure spermatogenesis. In this careful histomorphometric evaluation testis, we studied spermatogonial cells using molecular markers, determined combined duration meiotic spermiogenic phases, examined formation Sertoli cell barrier (tight junctions). We found at least nine generations propose a morphology-based nomenclature that is compatible with one used in higher vertebrates. number germ per cyst increased dramatically (1 to approximately 1360 cells) from undifferentiated spermatogonia type A early spermatids. phases 6 days, shorter periods among teleost fish investigated date. 9-fold during maturational cycle spermatogenic cysts stabilized phase ratio 100 spermatids (Sertoli efficiency). Similarly mammals, proliferation ceased phase, coinciding tight junctions between cells. Hence, events taking place puberty germinal epithelium mammals seem recapitulate "life history" each individual zebrafish.