Protective effects of melatonin on testis histology following acute torsion-detorsion in rats

BACKGROUND Testicular damage due to spermatic cord torsion may lead to infertility. It is probably because of changes in oxidative stress factors such as malondialdehyde. OBJECTIVE To investigate the protective effect of melatonin (MLT), as an antioxidant, on testicular damage induced by acute unilateral spermatic cord torsion and detorsion (T/D) in rats. MATERIALS AND METHODS In this experimental study, 48 adult male Wistar rats were randomly divided into three groups (8 rats/group): sham group underwent right scrotal surgery only., the T/D group underwent right testicular torsion (for 1 hr) and detorsion, and the melatonin group underwent right testicular torsion, received 25 µg/kg melatonin intraperitoneally immediately after surgery of T/D. Then the histological parameters and malondialdehyde (MDA) changes were evaluated. RESULTS Torsion and detorsion decreased the diameter of the tubules significantly compared to controls (p=0.003). Melatonin could increase the diameter, but it was not significant (p=0.26). The heights of the epithelium were constant in sham, T/D, and melatonin groups without any significant difference between groups (p=0.98). Based on Johnsen's score, spermatogenesis was normal in the sham group. The torsion significantly injured all lineage cells (p<0.001). There was no any spermatid or sperm in the seminiferous tubules. Melatonin improved the spermatogenesis significantly (p=0.02), but could not improve MDA level significantly (p=0.99). CONCLUSION Severe degenerative changes of testis were induced by acute unilateral spermatic cord torsion and detorsion in rats, but it had no effect on MDA level.