X射线胸部照射对小鼠精子发生的影响

目的:探讨X射线胸部照射对雄性成年小鼠精子发生的影响。方法:将24只健康雄性成年C57BL/6小鼠(6~8周龄)按照随机数表法分为X射线照射组(Radiation)和假照射组(Sham)，每组12只。胸部照射面积为1.5 cm × 2 cm，剂量率3.04 Gy/min，8 Gy/d，连续照射3 d，总剂量24 Gy，...

Effects of thoracic X-ray irradiation on the spermatogenesis of adult male mice

Objective To investigate the effect of thoracic X-ray irradiation on the spermatogenesis of adult male mice.Methods A total of 24 healthy adult male C57BL/6 mice (6-8 weeks old) were randomly divided into radiation group (Radiation) and sham-radiation group (Sham), 12 mice in each group. The area of thoracic irradiation was 1.5 cm×2 cm, and the dose rate was 3.04 Gy/min, 8 Gy/d for 3 consecutive days, 24 Gy in total. At 7 d and 21 d after thoracic irradiation, the bilateral testes and epididymal tails were stripped and the testicular index was calculated. The morphology of testis was examined by haematoxylin-eosin (HE) staining, then the diameter of seminiferous tubules and the thickness of seminiferous epithelium were measured. The sperms were collected from the bilateral epididymal tails for sperm counting. The level of apoptosis in testis and levels of apoptosis-related proteins were detected by TUNEL and Western blot, respectively.Results Compared with Sham group, the morphology of testis and epididymis was seriously damaged, the diameter of seminiferous tubules significantly decreased at 21 d after irradiation (t= 8.93,P<0.05), and the seminiferous epithelium significantly decreased at 7 d and 21 d after irradiation (t= 4.24, 12.77,P<0.05). In addition, the number of sperms significantly decreased (t= 4.30, 2.98,P<0.05). The number of TUNEL positive cells in the seminiferous epithelium significantly increased at 7 d and 21 d after irradiation (t= -2.73, -3.74,P<0.05). Meanwhile, the level of cleaved Caspase-3 protein significantly increased at 7 d and 21 d after irradiation (t= -2.96, -2.46,P<0.05). The concentrations of SCF and GDNF did not change at 7 d after irradiation, but were significantly increased at 21 d after irradiation (t= -10.46, -5.42,P<0.05).Conclusions The thoracic X-ray irradiation could lead to spermatogenesis disorder in male adult mice, and the induction of spermatogenic cell apoptosis and the secretory dysfunction of sertoli cells may be involved.