The Effects of Prednisolone on the Testes of Rabbits: Immunohistochemical and Ultrasonographic Observations

Objective: The aim of the study was to investigate the side effects of long-term high-dose administration of prednisolone on the testes of rabbits. Material and Methods: Twelve white male New-Zealand rabbits were included in our study. Prednisolone was administered intramuscularly to the first six rabbits at a dose of 20 mg/kg/week and Sodium Chloride solution (0.9%) to other six rabbits for 26 weeks. Rabbits were sacrificed under anesthesia.Testes were examined with ultrasonography and seminiferous tubules (ST) and capillary of testes were examined histopathologically. Results: Ultrasonographic examination of the testes revealed heterogeneous testis parenchyma invaded by numerous hyperechoic foci, representing testicular degeneration. Histological examination revealed thickening of the ST and basement membrane (BM) of capillary in the testes of rabbits and immunohistochemical examination revealed an increase of collagen IV fibers in the prednisolone-treated groups. The average thickness of the STBM of prednisolone-treated group and control group was 225.68 and 80.96 microns, respectively. Conclusion : In our study, a significant thickening of the BM and an increase in collagen IV fibers were noticed in rabbits administrated with prednisolone. These features demonstrate that prolonged administration of prednisolone may affect BM in tissues. These results indicate that ultrasonography of the testis may be useful in the differential diagnosis of testicular degeneration.