p,p’-DDE宫内暴露致雄性子代大鼠的生殖毒性

Reproductive Toxicity in Male Offspring Mice Following in Utero p,p'-DDE Exposure

[目的]探讨宫内暴露p,p’-DDE对雄性子代生殖毒性的影响。[方法]母鼠交配成功后,将其随机分为对照（玉米油）组和100 mg/kg p,p’-DDE染毒组,每组8只。染毒组于孕第8~15 d采用灌胃方式给予100 mg/kg p,p’-DDE处理,对照组孕鼠给予等容积玉米油。孕鼠自由分娩,观察仔鼠个数和出生性别,测量雄性仔鼠肛殖距及检查乳头存留情况;计算睾丸的脏器系数;利用计算机辅助精子分析系统测定雄性仔鼠的精子质量各相关指标;酶联免疫吸附法测定雄性子代血清睾酮水平。[结果]染毒组仔鼠肛殖距[（0.94±0.12）cm]较对照组仔鼠肛殖距[（1.11±0.13）cm]有所缩短,乳头存留率（34%）较对照组（0%）明显上调,精子数目[（50.00±4.62）×106个/m L],较对照组[（70.63±4.17）×106个/m L]明显降低,精子活力[（62.42±3.32）%],较对照组[（76.75±2.68）%]明显下降,差异均有统计学意义。2组雄性仔鼠雌雄比例、睾丸脏器系数、血清睾酮水平、睾丸重量差异均无统计学意义。[结论]宫内暴露p,p’-DDE可诱导雄性仔鼠出现雌性化特征,精子数目和活力下降,导致雄性子代生殖毒性。

[ Objective J To examine the effects of in utero exposure to p,p＇-DDE on reproductive toxicity in male offspring mice. [ Methods ] Pregnant rats were randomly divided into two groups of eight rats each and exposed to corn oil （control） or 100mg/kg p,p＇-DDE by garage from gestation day （GD） 8 to 15. The pregnant rats were allowed natural delivery, and the counts and gender of pups in the two groups were observed. The reproductive indices in male pups were recorded including nipple retention, anogenital distance （AGD）, testicular organ coefficient, and sperm parameters by computer assisted sperm analysis, as well as serum concentration of testosterone by enzyme linked immunosorbent assay （ELISA）. [ Results ] The anogenital distance, sperm count, and sperm motility of the male pups in the p,p＇-DDE-treated group were significantly lowered when compared with those of the control group [（0.94± 0.12）cm vs. （ 1.11 ± 0.13）cm; （50.00± 4.62）× 10^6 sperm/ml vs. （70.63± 4.17） ×10^6 sperm/ml; （62.42 ±3.32）% vs. （76.75± 2.68）%, respectively], and the thoracic nipple retention was significantly increased （34 % vs. 0%） （all Ps 〈 0.05）. There were no significant differences in sex ratio of pups, testicular organ coefficient, serum testosterone level, and testicular weight. [ Conclusion ] The results demonstrate that in utero exposure to p, p＇-DDE may lead to reproductive toxicity in male offspring and present estrogenic effects, including decreased sperm count and sperm motility.