ortho-Substituted polychlorinated biphenyl (PCB) congeners (95 or 101) decrease pituitary response to thyrotropin releasing hormone
ortho-Substituted polychlorinated biphenyl (PCB) congeners (95 or 101) decrease pituitary response to thyrotropin releasing hormone
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DOI：
10.1016/s0378-4274(03)00203-0
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发表时间：
2003-09-30
影响因子：
3.5
通讯作者：
Hansen, LG
中科院分区：
文献类型：
--
作者：
Khan, MA;Hansen, LG
多氯联苯化合物（PCBs）是一种全球性的环境污染物，可引起人类和野生动物内分泌系统的紊乱。最近，我们报道了急性暴露于ortho-PCB同系物95（2，3，6 - 2 '，5'）或101（2，4，5，-2 '，5'）导致发育中大鼠下丘脑-垂体-甲状腺（HPT）轴的性能变化，其机制尚不清楚。HPT轴的功能进行了评估，通过使用促甲状腺激素释放激素（TRH）测试后，急性接触多氯联苯95或101。断奶雌性大鼠接受PCBs 95或101腹腔注射（ip）在32毫克/公斤，连续2天，合成TRH后48小时，最后一次剂量。接触这两种同系物后，血清甲状腺素（T-4）水平下降。在PCB 95处理的大鼠，血清促甲状腺激素（TSH）水平升高，响应TRH，但只有40%的控制响应TRH。血清催乳素（PRL）、下丘脑多巴胺（DA）、甲状腺形态学或上皮细胞增殖未见显著变化。这表明，这些同源物，干扰HPT轴引起的垂体和甲状腺TRH刺激的反应低于正常。(C)2003爱思唯尔爱尔兰有限公司保留所有权利。
Polychlorinated biphenyl compounds (PCBs) are global environmental contaminants that cause disruption of the endocrine system in humans and wildlife. Recently, we reported that acute exposures to ortho-PCB congeners 95 (2,3,6-2',5') or 101 (2,4,5,-2',5') causes changes in the performance of the hypothalamo-pituitary-thyroid (HPT)-axis in developing rats through mechanism(s) not yet clear. The functionality of the HPT-axis was evaluated by using the thyrotropin releasing hormone (TRH) test following acute exposure to PCBs 95 or 101. Weanling female rats received PCBs 95 or 101 intraperitoneally (ip) at 32 mg/kg for 2 consecutive days and synthetic TRH was given 48 h after the last dose. Serum thyroxine (T-4) levels decreased following exposure to both the congeners. In PCB 95-treated rats, serum thyroid stimulating hormone (TSH) levels were elevated in response to TRH, but were only 40% of the control response to TRH. No significant changes were seen in serum prolactin (PRL), hypothalamic dopamine (DA), thyroid gland morphology, or epithelial cell proliferation. It is suggested that these congeners, interfere with the HPT-axis by causing a subnormal response of the pituitary and thyroid to TRH stimulation. (C) 2003 Elsevier Ireland Ltd. All rights reserved.