Li Xuezheng, Li ChunMei, Suzuki Akira K, Watanabe Gen, Taneda Shinji, Taya Kazuyoshi
Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo 183-8509, Japan.
Biosci Biotechnol Biochem. 2009 Sep;73(9):2018-21. doi: 10.1271/bbb.90204. Epub 2009 Sep 7.
To examine the endocrine disruptive effects of 3-methyl-4-nitrophenol (4-nitro-m-cresol; PNMC) in diesel exhaust particles (DEP), the rat Hershberger assay was carried out using castrated immature rats. Castrated 28-d-old immature male rats were implanted with a 5-mm-long silastic tube containing crystalline testosterone and injected with PNMC subcutaneously at doses 1, 10, or 100 mg/kg for 5 consecutive d. The weights of the livers significantly decreased in the 10 and 100 mg/kg PNMC treatment groups as compared with the control group. The weights of the seminal vesicles significantly increased in the 10 mg/kg PNMC treatment group as compared with the control group. The weights of the Cowper's glands were significantly increased in 1 mg/kg PNMC treatment group compared with the control group. The concentrations of plasma testosterone significantly increased in the 10 and 100 mg/kg PNMC treatment groups, indicating that PNMC induced accumulation of bioactive testosterone released from the implanted tube in circulation. Plasma follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels significantly decreased under all the doses in the PNMC treatment groups, indicating that PNMC acts on the hypothalamus-pituitary axis.
为了研究柴油尾气颗粒（DEP）中的3-甲基-4-硝基苯酚（4-硝基间甲酚；PNMC）的内分泌干扰作用，使用去势未成熟大鼠进行了大鼠赫什伯格试验。对28日龄去势未成熟雄性大鼠植入一根含有结晶睾酮的5毫米长硅橡胶管，并连续5天皮下注射剂量为1、10或100毫克/千克的PNMC。与对照组相比，10和100毫克/千克PNMC处理组的肝脏重量显著降低。与对照组相比，10毫克/千克PNMC处理组的精囊重量显著增加。与对照组相比，1毫克/千克PNMC处理组的考珀氏腺重量显著增加。10和100毫克/千克PNMC处理组的血浆睾酮浓度显著增加，表明PNMC诱导了植入管中释放的生物活性睾酮在循环中的积累。PNMC处理组在所有剂量下血浆促卵泡激素（FSH）和促黄体生成素（LH）水平均显著降低，表明PNMC作用于下丘脑-垂体轴。
