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目的 探讨十氯酮对雄性秀丽隐杆线虫精细胞的毒性效应及其与氧化应激损伤作用的关系.方法 幼虫 1 期线虫分别暴露于4 个剂量十氯酮(0.02、0.20、2.00、20.00 μg/L)、对照组(M9 溶液),48 h 后,计数后代数目和观测世代时间;通过二氢荧光素乙酰乙酸(CM-H2DCFDA)探针法检测线虫体内活性氧(ROS)水平;荧光显微镜观测线虫远端顶细胞(DTC)荧光强度;二脒基苯基吲哚(DAPI)染色后计数性腺有丝分裂区生殖细胞数;显微镜明场下观测线虫精子畸形率和体外活化率.结果 十氯酮高剂量组秀丽隐杆线虫后代数目为(255.00 ± 13.72)个,明显低于对照组(335.60 ± 21.31)个;十氯酮高剂量组秀丽隐杆线虫世代时间为(69.60 ± 1.96)h,长于对照组(55.80 ± 1.94)h,差异有统计学意义(P ＜ 0.05).与对照组比较,十氯酮2.00、20.00 μg/L 组线虫体内活性氧水平升高,各剂量十氯酮组线虫远端顶细胞荧光强度降低(P ＜ 0.05).对照组线虫有丝分裂区生殖细胞数目为(87.90 ± 3.75)个、精子畸形率为( 12.70 ± 1.16) ％、体外活化率为( 77.00 ± 9.82) ％, 20.00 μg/L 十氯酮组线虫有丝分裂区生殖细胞数目[( 47.90 ± 5.42)个]下降、精子畸形率[(84.00 ± 7.29) ％]明显上升、体外活化率[(8.70 ± 2.41) ％]明显下降.结论 氧化应激损伤可能是十氯酮暴露后引发生殖毒性作用的重要机制.“,”Objective To investigate toxic effects of chlordecone on sperm cells of Caenorhabditis elegans (C. elegans) and its relationship with oxidative stress injury. Methods The nematodes of stage L1 were exposed to chlordecone at four dosages (0.02, 0.2, 2 and 20 μg/L) for 48 hours and those of blank control were treated with M9 solution; then the number of offspring was counted and the generation time was observed for all the nematodes. The level of reactive oxygen species (ROS) in the nematodes was detected with 5-(6)-chloromethyl-2′,7′-dichlorodihydrofluorescein diacetate (CM-H2DCFDA) probe. The fluorescence intensity of distal tip cells (DTC) of JK2868 nematodes was observed with fluorescence microscopy. The number of gonadal mitosis was counted after dianamidophenylindole (DAPI) staining. The sperm deformity rate and in vitro activation rate of the nematodes were determined with microscopic observation. Results The number of C. elegans progeny in the high-dose chlordecone group was 255.00 ± 13.72 and significantly higher than that in the control group (335.60 ± 21.31); the generation time of the high-dose chlordecone group was 69.60 ± 1.96 hours and significantly longer than that of the control group (55.80 ± 1.94 hours) (both P ＜ 0.05). Compared with those of the control group, the level of ROS in the nematodes was higher but the fluorescence intensity in DTC was lower significantly for the nematodes exposed to moderate and high dose chlordecone (both P ＜ 0.05). In comparison with those in the control group, decreased number of germ cells in the mitotic area (47.90 ± 5.42 vs. 87.90 ± 3.75), increased rate of sperm abnormality (84.00％ ± 7.29％ vs. 12.70％ ± 1.16％) and decreased rate of sperm activation in vitro (8.70％ ± 2.41％ vs. 77.00％ ± 9.82％) were observed in the nematodes exposed to 20.00 μg/L chlordecone. Conclusion Oxidative stress injury may be an important mechanism of genotoxicity induced by chlordecone in Caenorhabditis elegans.