The Effects of Long-term Administration of Tramadol on Epididymal Sperm Quality and Testicular Tissue in Mice

Objective- The objective of the present work was to investigate the effects of tramadol administration on sperm quality and testicular tissue in mice. Design- Experimental study Animal- Sixty-three mature male mice Procedures- Mice were randomly divided into three experimental groups (n=21) and the following treatments were intraperitoneally administered, 3 times a week, for 6 weeks: Control male mice were given physiological saline. Two other groups were given different doses of tramadol including 10 mg/kg (group T1) and 20 mg/kg (group T2). Seven mice in each group were sacrificed at weeks 3, 6 and 12 after the beginning of treatments. Left testes were removed for epiddydimal sperm quality and histopathological evaluations. Results- The results showed that sperm concentration, motility and vitality in group T1 and T2 were significantly decreased (P<0.05) in comparison with group control at weeks 3 and 6, but the mentioned parameters were recovered significantly at week 12. Microscopic examinations revealed that tramadol in both doses damaged the testicular tissue at weeks 3 and 6, so that more degenerative changes were observed in group T2 at week 6. Most of histopathological parameters returned to the normal structure in groups T1 and T2, at week 12. Conclusion and clinical relevance- According to the results of present study, it can be concluded that long-term administration of tramadol have adverse effects on sperm quality and testicular tissues and these effects are dose dependant. Also the negative effects of tramadol on testes are reversible. Key words- Tramadol, Testis, Histopathology, Sperm quality, Mice.