染砷大鼠睾丸生精细胞凋亡的变化

目的观察不同剂量的三氧化二砷（As2O3）对成年大鼠生精细胞凋亡的影响。方法40只健康雄性SD大鼠随机分成4组，分别为0．375mg／kg、0．75mg／kg、1．5mg／kg3个染毒组和对照组，灌胃法连续给药16周后对各组大鼠进行睾丸脏器系数、精子头计数，并计算每日精子生成量（DSP）。采用甲基绿—派诺宁染色法和TUNEL原位细胞杂交方法检测大鼠生精细胞凋亡情况。结果①中剂量组（0．75mg／kg）和高剂量组（1．5mg／kg）睾丸精子头计数和DSP均低于对照组（P〈0．05）；②与对照组相比，中剂量组和高剂量组生精细胞凋亡指数（AI）均显著升高（P〈0．01）；③生精细胞凋亡指数与每日精子生成量呈负相关（r=-0．563，P〈0．01）。结论一定剂量的As2O3可通过促进生精细胞凋亡而导致精子生成量的减少，产生生殖毒性。

Study of As2O3 on Apoptosis of Spermatogenic Cells of Rat Testis

Objective To investigate the effect on the apoptosis of spermatogenic cells in adult rats with different doses of arsenic （As2O3）. Methods 40 healthy male Sprague-Dawle rats were divided randomly into four groups and they were administered respectively with 0 （control group）, 0. 375, 0. 75 and 1.5 mg · kg^-1 body weight of As2O3 by intragastric administration consecutively for 16 weeks. The numbers of testicular sperm head were counted and the coefficient of testicular viscera , daily sperm production was calculated in every group. The apoptosis of germ cell were assessed by in situ terminal deoxynucleotityl transferase mediated dTUP nick end labeling（TUNEL） technique and methyl green-pyronin staining method. Results ①In the testes of As2O3-treated rats,The coefficient of testicular viscera , the number of testicular sperm head and daily sperm production in mid and large-dose groups decreased significantly than that in the control（P〈0. 05） ;② the apoptosis index of germ cell（AI） significantly increased compared with that in the control group （P〈0. 01） ;③There were negative correlation between the apoptosis index of germ cell（AI） and the content of serum arsenic （r=-0. 563,P〈0.01）. Conclusions The apoptosis of spermatogenic cells can be aggravated after As2O3 administration in male rats, it may reduce the sperm production and lead to the reproduction toxicity.