OBJECTIVE: To investigate the antioxidant effects of nebivolol in spermatogenic cells against apoptotic and testicular inflammation in torsion-detorsion injury in rats by using TUNEL assay and immunohistochemical methods. STUDY DESIGN: Forty male rats were categorized into 4 groups: control group (abdominal wall was opened and closed), torsion group (left testis was rotated 720° clockwise around longitudinal axis of spermatic cord for 2.5 hours), torsion/detorsion group (after 2.5 hours of torsion process, the suture that fixed the testis to the tunica dartos was cut off for detorsion for the following 3 hours), and torsion/detorsion+nebivolol group (2.5-hour ischemia followed by administration of 10 mg/kg nebivolol 30 minutes prior to a 3-hour torsion/ detorsion). Biochemical assays (MDA, SOD, CAT, GSH) and histopathologic results were examined in the testicular tissue. TUNEL assay method was used for DNA fragmentation analysis in testicular seminiferous tubule sections. RESULTS: Nebivolol treatment seemed to prevent the increase in MDA levels of torsion-detorsion–induced testis. Statistically, SOD, CAT, and GSH activities were significantly decreased in the torsion/detorsion group, while they were increased in the torsion/detorsion+nebivolol group. In the torsion and torsion/detorsion groups, an increase in apoptosis was observed in the germ cells in the tubules, and it was seen that the application of nebivolol decreased germ cell apoptosis. CONCLUSION: Unilateral testicular torsion-detorsion causes testicular damage to the ipsilateral testis as evidenced by biochemical and apoptotic changes in the tissues and retains the morphological structure in the testes after nebivolol administration, after testicular torsion-detorsion damage, and decreased apoptotic index and inflammation. © Science Printers and Publishers, Inc.