Investigation of the effect of n-nitrozo-n-ethylurea on zebra fish (danio rerio) testicular histology

N-Nitrozo compounds have been known since the beginning of the 20th century, but are more remarkable since the 1950s. N-Nitrozo-N-Ethylurea (ENU) is an important substance used today as a preservative in food products. As a result of research on experimental animals, toxic, teratogenic, mutagenic and carcinogenic effects have been reported. The aim of this study was to investigate the histopathological effects of N-Nitrozo-N-Ethylurea on the testicular tissue of zebrafish. This study was divided into 5 groups as control and experimental groups and the experimental groups were exposed to ENU doses of 0.25 mM, 0.50mM Tissue samples were stained with Hemotoxylin&Eosin and examined under light microscope. Depending on the increase in dose and exposure time, degeneration in testicular tissue of the experimental groups, seminiferous tubules, vacuolization in seminiferous tubules, opening in seminiferous tubules, deterioration of seminiferous tubule integrity, bleeding in the cell clusters in the spermatogenetic series, disruption in the number of cells and distribution in the seminiferous tubules area, decreases in the number of spermatogenetic cells. vacuolization in spermatogenic cell groups, hypertrophy in some cells and apoptosis in some spermatogonium cells. In addition, thickening of the connective tissue around the seminiferous tubule, an increase in the number of sperms depending on the dose group, and in some places, were detected in piconotic cells. The findings revealed that male zebra fish exposed to ENU caused negative changes in the testicular tissues.