[Estrogen-like activity of 4-nonylphenol and bisphenol in immature SD rats].
OBJECTIVE
To investigate the estrogen-like activity of 4-NP and BPA in the immature SD rats.


METHODS
The vehicle, ethinyl estradiol (EE, 0.3 mg/kg, positive control), 4-NP (50 mg/kg, 100 mg/kg, 200 mg/kg), bisphenol (BPA, 200 mg/kg, 400 mg/kg, 600 mg/kg) were given orally (by gavage) q.d. to immature female Sprague-Dawley rats on the 21st, 22nd, 23rd postnatal days. The rats were sacrificed 24 hours after the last administration. Uterine wet weight, uterine/body weight ratio, height of the luminal epithelium, thickness of the myometrium and protein level of proliferating cell nuclear antigen (PCNA) of rat uterine were analysed by one-way ANOVA.


RESULTS
In animal experiments, uterine wet weight and uterine/body weight ratio were significantly higher in the 4-NP 200 mg/kg and 100 mg/kg, BPA 600 mg/kg and 400 mg/kg (P < 0.05). Height of luminal epithelium, thickness of myometrium, as well as protein level of PCNA of rat uterine were significantly increased in the three groups of 4-NP, the three groups of BPA, and the mixture group (P < 0.05), and a dose-response relationship was observed.


CONCLUSIONS
4-NP and BPA had weak estrogen-like activities. They were the main environmental endocrine disruptors, and could influence the healthy of immature animals and children.
Lu
Junping
J
Children's Hospital of Fudan University, Shanghai 200032, China. ljp159@hotmail.com
Cai
Depei
D
D000818:Animals; D001559:Benzhydryl Compounds; D004305:Dose-Response Relationship, Drug; D052244:Endocrine Disruptors / Q000633:toxicity*; D004968:Estrogens, Non-Steroidal / Q000633:toxicity*; D005260:Female; D010636:Phenols / Q000633:toxicity*; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D014599:Uterus / Q000473:pathology*; D000098826:Bisphenol A Compounds
D001559:Benzhydryl Compounds; D052244:Endocrine Disruptors; D004968:Estrogens, Non-Steroidal; D010636:Phenols; D018809:Proliferating Cell Nuclear Antigen; C041594:4-nonylphenol; C006780:bisphenol A; D000098826:Bisphenol A Compounds