Effects of methotrexate administration on testis histomorphometrical features of rats

Introduction: Methotrexate (MTX) is a chemotherapeutic agent that used for the treatment of a variety of tumors and inflammatory diseases. Methotrexate cause defective cogenesis, spermatogenesis, fertility impairment and different pathological changes on testis laboratory animals. The aim of this study was to investigate the effect of methotrexate administration on morphometerical changes in the testis of adult rat. Methods: In this experimental study 40 male wistar rats were selected and randomly divided into four groups. Experiment groups were received 1mg/kg MTX (IP) per week for two and four consequence week, respectively. However, control groups just received normal saline (IP) for 14 and 28 consequence days, respectively. The testis were sampled after passing of above times and stained by H & E technique. Then diameter of seminiferous tubules, thickness of interstitial tissue, and thickness of testicular capsule, were studied. Data were analyzed by analysis of variance. Results: Our study showed that methotrexate had destructive effects on testis tissue and spermatogenesis in test group compared to control group. Results showed that within 28 days after methotrexate administration diameter of seminiferous tubules and thickness of epithelium of seminiferous tubules significantly decreased (P<0.05), but thickness of interstitial tissue and thickness of testicular significant increased (P<0.05) compared to controls. Conclusion: Results showed that methotrexate administration causes decline in spermatogenesis and significant changes in diameter of seminiferous tubules, thickness of epithelium of seminiferous tubules, thickness of interstitial tissue, and thickness of testicular capsule in rat testis tissue. These changes may via the reducing of cell divide and toxic effects of methtrexate.