OBJECTIVETo investigate the protective effect of verapamil and hypothermia on the spermatogenesis of rats after testicular torsion.

METHODSSixty healthy pubertal male Sprague-Dawley rats were equally divided into 5 groups: A (testis torsion), B (testis torsion + verapamil), C (testis torsion + hypothermia), D (testis torsion + verapamil + hypothermia) and E (control). After treatment, the left testis was removed for the observation of the histological changes under the microscope and measurement of the percentage of apoptotic cells by flow cytometry.

RESULTSHE staining showed disordered arrangement, reduced layers and decreased number of spermatogenic cells, apoptotic bodies, necrosis and partial invasion of inflammatory cells in all the groups but E, most obvious in Group A. The apoptosis rates of germ cells in Groups A, B, C, D and E were (32.11 +/- 2.20)%, (20.18 +/- 1.50)%, (20.02 +/- 1.90)%, (13.75 +/- 1.40)% and (8.56 +/- 0.90)%, respectively, and the Makler scores in the 5 groups were (14.47 +/- 1.35), (15.45 +/- 0.75), (15.48 +/- 0.75), (16.22 +/- 0.72) and (19.60 +/- 0.56), respectively, both with statistically significant differences (P < 0.01).

CONCLUSIONThe increased apoptosis of germ cells after testicular torsion-and-reposition may reduce the spermatogenesis of the testis. Either verapamil or local hypothermia can enhance testicular resistance against injuries, and the combination of the two can more efficiently prevent the germ cells from apoptosis.