Furukawa Satoshi, Tsuji Naho, Sugiyama Akihiko
Biological Research Laboratories, Nissan Chemical Corporation, 1470 Shiraoka, Shiraoka-shi, Saitama 349-0294, Japan.
Veterinary Clinical Pathology, Faculty of Veterinary Medicine Okayama University of Science, 1-3 Ikoinooka, Imabari, Ehime794-8555, Japan.
J Toxicol Pathol. 2019 Jan;32(1):1-17. doi: 10.1293/tox.2018-0042. Epub 2018 Oct 15.
The placenta plays a pivotal role in fetal growth, and placental dysfunction and injury are associated with embryo/fetal toxicity. Histological examination of the rat placenta for safety evaluation provides valuable clues to the mechanisms of this toxicity. However, the placenta has specific and complex biological features unlike those of other organs, and placental structure dramatically changes depending on the time during the gestation period. Thus, time-dependent histopathological examination of the rat placenta should be performed based on the understanding of normal developmental changes in morphology and function. The placentas of rats and humans are both anatomically classified as discoid and hemochorial types. However, there are differences between rats and humans in terms of placental histological structure, the fetal-maternal interface, and the function of the yolk sac. Therefore, extrapolation of placental toxicity from rats to humans should be done cautiously in the evaluation of risk factors. This review describes the development, morphology, physiology, and toxicological features of the rat placenta and the differences between the rat and human placenta to enable accurate evaluation of reproductive and developmental toxicity in studies.
胎盘在胎儿生长过程中起着关键作用，胎盘功能障碍和损伤与胚胎/胎儿毒性相关。对大鼠胎盘进行组织学检查以评估安全性，可为这种毒性的机制提供有价值的线索。然而，胎盘具有与其他器官不同的特定且复杂的生物学特性，并且胎盘结构会根据妊娠期的不同时间发生显著变化。因此，应在了解大鼠胎盘形态和功能的正常发育变化的基础上，对其进行时间依赖性组织病理学检查。大鼠和人类的胎盘在解剖学上均归类为盘状和血绒毛膜类型。然而，大鼠和人类在胎盘组织结构、胎儿 - 母体界面以及卵黄囊功能方面存在差异。因此，在评估风险因素时，应谨慎地将大鼠胎盘毒性外推至人类。本综述描述了大鼠胎盘的发育、形态、生理和毒理学特征，以及大鼠和人类胎盘之间的差异，以便在研究中准确评估生殖和发育毒性。
