STUDY ON THE EFFECTS OF CO-PLANAR PCBS ON THE FUNCTION AND MORPHOLOGY OF FEMALE GENITAL ORGANS

在实验(实验)I中，雌性SD大鼠每天口服玉米油或3，3‘，4，4’，5-五氯联苯(PCB126)的1和3μg/kg/天(PCB126)后交配和受孕。每天持续给药，直到妊娠期间分娩后20天。染毒剂量为3μg/kg/d时，PCB126可延迟小鼠阴道开放时间，减少首次排卵时排出的卵母细胞数。在实验中怀孕雌性SD大鼠于妊娠第15天(GD15)单次灌胃玉米油或10、100μg/kg多氯联苯。单次注射10或100μg/kg的PCB126可显著延缓VO，减少子代首次排卵时排出的卵母细胞数。大多数子代在实验中暴露于100μg/kg。在这些子代中，II显示VO与第一次排卵不同步，排卵时子宫重量减轻。在两个实验中。I和II，暴露的雌性后代表现为尿道下裂。在实验中怀孕的雌性SD大鼠在GD8或GD15上单次灌胃玉米油或1和10μg/kg的PCB126。10μg/kg染毒可诱发雌性子代尿道下裂。在另一项实验中表明，哺乳期暴露于多氯联苯126并不会导致雌性后代出现尿道下裂。在20日龄和30周龄，暴露于10μg/kg多氯联苯的雌性仔鼠表现出持续发情和卵巢重量下降。

In experiment (Exp.).I, female SD rats copulated and conceived after daily oral administration for 2 weeks of either corn oil or 1 and 3 μg/kg/day of 3, 3', 4, 4', 5-pentachlorobiphenyl (PCB 126), a congener of coplanar PCBs, respectively. Daily administration was continued until 20 days alter delivery through the gestational period. Exposure to PCB 126 delayed vaginal opening (VO) and reduced the number of oocytes shed at first ovulation at a dose of 3 μg/kg/day. In Exp. II, pregnant female SD rats were single-administered orally either corn oil or 10 and 100 μg/kg of PCB 126 on gestational day 15 (GD 15). A single injection of 10 or 100 μg/kg of PCB 126 to the dams delayed VO and reduced the number of oocytes shed at the first ovulation in their offspring significantly. Most offspring exposed to 100 μg/kg in Exp. II showed VO unsynchronized with the first ovulation in these offspring and reduced uterine weight at the ovulation. In both Exps. I and II, exposed female offspring showed hypospadias. In Exp. III, pregnant female SD rats were single-administered orally either corn oil or 1 and 10 μg/kg of PCB 126 on GD 8 or GD15. Hypospadias was induced in the female offspring exposed to 10 μg/kg. In additional experiment indicate d that lactational exposure to PCB 126 did not induce hypospadias in female offspring. Female offspring exposed to 10 μg/kg of PCB 126 on GD15 showed continuous estrus and reduced ovarian weight at 20 weeks and 30 weeks of age.