Department of Human Anatomy & Cell Science, University of Manitoba, Winnipeg, Manitoba, Canada.
Mol Cell Endocrinol. 2013 Mar 10;367(1-2):98-108. doi: 10.1016/j.mce.2012.12.022. Epub 2013 Jan 4.
Ewes were exposed to sewage sludge-fertilized pastures in a study designed investigate pre-conceptual and/or gestational exposure to environmental chemicals. The in utero impact on fetal thyroid morphology and function at day 110 (of 145) of pregnancy was then determined. Pre-conceptual exposure increased the relative thyroid organ weights in male fetuses. The number of thyroid follicles in thyroids of fetuses after pre-conceptual or gestational exposure was reduced. This correlated with an increase in Ki67 positive cells. Pre-conceptual exposure to sewage sludge reduced small blood vessels in fetal thyroids. Thyroid tissues of exposed fetuses contained regions where mature angio-follicular units were reduced exhibiting decreased immunostaining for sodium-iodide symporter (NIS). Fetal plasma levels of fT3 and fT4 in exposed animals, however, were not different from controls suggesting compensatory changes in the thyroid gland to maintain homeostasis in exposed fetuses. The regional aberrations in thyroid morphology may impact on the post-natal life of the exposed offspring.
在一项旨在研究环境化学物质孕前和/或妊娠期暴露的研究中，母羊接触了经过污水污泥施肥的牧场。然后确定了宫内对妊娠第 110 天（145 天妊娠）胎儿甲状腺形态和功能的影响。孕前暴露增加了雄性胎儿的相对甲状腺器官重量。孕前或妊娠期暴露后的胎儿甲状腺滤泡数量减少。这与 Ki67 阳性细胞的增加相关。孕前接触污水污泥减少了胎儿甲状腺中的小血管。暴露胎儿的甲状腺组织中存在成熟的血管滤泡单位减少的区域，表现为钠碘转运体（NIS）免疫染色减少。然而，暴露动物的胎儿血浆 fT3 和 fT4 水平与对照组无差异，表明甲状腺在暴露胎儿中维持内稳态的代偿性变化。甲状腺形态的区域性异常可能会影响暴露后代的产后生活。
