孕期及哺乳期邻苯二甲酸二(2-乙基己基)酯经口染毒对雄性仔鼠生殖发育的影响

目的观察邻苯二甲酸二(2-乙基已基)酯(DEHP)对雄性仔鼠的生殖发育毒性作用。方法采用围生期毒性试验的研究方法,将清洁级SD大鼠随机分为阴性对照组(玉米油)和4个DEHP染毒组(125、250、500、1000mg/kg),采用宫内及哺乳期[受孕后第2天～仔鼠出生后第21天(PND21)]经口灌胃的方式染毒。记录比较雄性仔鼠肛殖距、不同发育阶段雄性仔鼠体重、睾丸、附睾重量、仔鼠出生后第50天(PND50)附睾尾精子总数、精子活率及精子畸形数。结果 125～500mg/kg组不同发育阶段仔鼠体重随染毒剂量增加而增加,500mg/kg组PND21体重与对照组比较,差异有统计学意义(P0.01),1000mg/kg组体重均低于同发育阶段对照组,PND21体重与对照组比较,差异具有统计学意义(P0.05)。1000mg/kg组不同发育阶段仔鼠睾丸重量明显降低,与对照组比较,差异有统计学意义(P0.01),附睾重量与对照组比较差异均无统计学意义(P0.05)。仔鼠出生后4天肛殖距不同程度缩短,除125mg/kg组外,其余各剂量组与对照组比较,差异均有统计学意义(P0.01)。PND50雄性仔鼠精子总数、精子活率均不同程度降低,精子畸形率不同程度增高,1000mg/kg组与对照组比较,差异有统计学意义(P0.05)。结论母鼠孕期及哺乳期暴露DEHP可影响雄性仔鼠生长、生殖发育。

Reproductive and Developmental Toxicity to Male Offspring Rats with Utero and Lactational Exposure to DEHP

Objective To observe the reproductive and developmental toxicity of phthalate (2-ethylhexyl) ester (DEHP) to male offspring. Methods The perinatal toxicity tests were used as research methods. SD rats were randomly divided into negative control group (corn oil) and four DEHP exposure groups (125, 250, 500 and1 000 mg/kg), and exposed to DEHP through garage during the period of intra-uterine and breast-feeding. The male offspfing's anogenitai distance, the weight of body, testis and epididymis were measured at different developmental stages, as well as the epididymal sperm number, sperm motility rate and the number of sperm abnormality at the 50th day after birth (PND50). Result The body weights of offspring increased with the exposure doses at different developmental stages among the DEHP exposure doses of 125-500 mg/kg, the body weight of 500 mg/kg group was higher at PND21 compared with the control group significantly (P<0.01), the body weight of 1 000 mg/kg group were lower than the same developmental stage of the control group, and showed significant difference (P<0.05) compared with control group at PND21. The testis weight of offspring at different developmental stages in 1 000 mg/kg group was significantly lower compared with the control group (P<0.01), epididymal weight compared with the control group had no significant difference (P>0.05). Four days after birth, the anogenital distance reduced at different degree, in addition to 125 mg/kg group, the rest groups showed significant differences compared with control group (P<0.01). At PND50, the total number of sperm and sperm motility of male offspring reduced to varying degrees, sperm deformity rate increased to varying degrees, 1 000 mg/kg group had a significant difference compared with the control group (P<0.05). Conclusion Female rats exposed to DEHP during pregnancy and lactation can affect the growth and reproductive development of male offspring, this may be one of the causes leading to the adult male infertility.