Transfer of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) via placenta and milk, and postnatal toxicity in the mouse
Transfer of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) via placenta and milk, and postnatal toxicity in the mouse
复制标题
2,3,7,8-四氯二苯并-对二恶英 (TCDD) 通过胎盘和乳汁的转移以及小鼠的产后毒性
作者：
H. Nau;R. Bass;D. Neubert
摘要：2,3,7,8-四氯二苯并-对-二恶英（TCDD）被发现可以通过哺乳期母亲有效地转移给小鼠新生儿和后代。在出生后的前 2 周，幼仔通过乳汁接受 TCDD 剂量，按体重计算，其剂量与产前母体的 TCDD 相似。 TCDD 在后代中的分布（肝脏中含量高，其他组织中含量低）与母体中的分布相似。 母体 TCDD 水平在哺乳期迅速下降，而哺乳仔犬中的组织水平增加，导致后代组织水平大大超过其母亲在各自的时期的组织水平。出生后 3 周。研究了在妊娠第 14-17 天接受治疗的母亲和未经治疗的养母喂养的幼崽的产后发育。产后死亡率增加。幸存的动物没有表现出明显的异常发育迹象，尽管每窝幼崽数量的减少可能有助于这种明显的正常发育。在小型啮齿动物中，排泄到乳汁中是消除母体 TCDD 的主要途径。对于人类是否同样如此尚不清楚，但母乳中 TCDD 水平的测量可能是评估人类接触该物质的适当且实用的方法。
Abstract2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) was found to be efficiently transferred to mouse neonates and offspring by lactating mothers. During the first 2 postnatal weeks the pups received doses of TCDD via the milk which were, on a body weight basis, similar to those which had been administered prenatally to their mothers.The distribution of TCDD in the offspring (high in liver, low in other tissues) was similar to that found in the maternal organism.Maternal TCDD levels rapidly decreased during the lactation period while tissue levels in the nursing pups increased, resulting in offspring tissue levels which greatly exceeded those of their mothers at the respective 3-week periods after birth.The postnatal development of pups from mothers treated on days 14–17 of gestation and nursed by untreated foster mothers was studied. Postnatal mortality was increased. Surviving animals did not exhibit visible signs of abnormal development, although the reduced number of pups per litter may have contributed to this apparently normal development.In small rodents excretion into milk constituted a major pathway for the elimination of maternal TCDD. Whether the same holds true for man is still unknown, but the measurement of TCDD levels in breast milk may be an appropriate and practical method for the assessment of human exposure to this substance.