低剂量苯45d染毒致小鼠的生殖毒性

Reproductive Toxicity of Low-dose Benzene Exposure for 45 days in Female Mice

目的研究低剂量苯(50 mg/kg.d)45 d染毒对成年雌性小鼠生殖系统的影响,探讨苯的生殖毒性。方法清洁级昆明种雌性成年小鼠24只随机分为苯处理组与溶剂对照组,苯处理组用苯(50 mg/kg.d)灌胃,溶剂对照组用植物油灌胃,连续灌胃45 d,第15~21 d用清洁级昆明种雄性小鼠按1:2与雌鼠进行合笼交配,之后分笼饲养,持续染毒,期间孕鼠陆续分娩胎仔,直至染毒结束后剖杀动物,检测生殖毒性指标。结果与对照组相比,苯处理组动物的体重增长速度减慢,在第21 d和第45 d差异有统计学意义(P均<0.05);与对照组相比,苯处理组的肝脏脏器系数明显降低(P<0.05),胎仔的体重、身长和尾长减小,差异均有统计学意义(P均<0.05);苯处理组的卵巢组织镜下可见病理改变。结论低剂量苯(50 mg/kg.d)45 d连续染毒对雌鼠生殖系统具有损伤作用。

Objective To study the reproductive toxicity of low - dcse benzene （50mg/kg- d） exposure for 45 days in adult female mice. Methods Twenty - four female mice were randomly divided into the benzene - treated group and the con- trol group. The mice in the benzene- treated group were extgesed to benzene at 50mg/kg· d by intragastric administration for 45 days. The mice in the control group were administered with vegetable oil. They were mated with male mice at the ratio of 2 ： 1 from the Day 15 to 21, and then were fed in separate cages and continually extx^sed to benzene or vegetable oil. The female mice were sacrificed at the end of the experiment to detect the indicators of reproductive toxicity. Results Compared with the con- trol group, the growth of the mice in the benzene- treated group was retarded. The body weights of the mice at Day 21 and Day 45 were significantly decreased （P 〈 0.05）. The organ coefficient of the liver was statistically lower （P ~ 0.05）. The bodyweight, body length and tail length of the fetal mice in the benzene - treated group were statistically decreased （ P 〈 O. 05）. Pathological changes could be found in the ovarian tissue of the mice in the benzene- treated group. Conclusions Consecutive exposure to benzene at 50mg/kg＂ d for 45 days may produce reproductive toxicity in female mice.