Lorente C A, Miller S A
J Nutr. 1977 Oct;107(10):1816-21. doi: 10.1093/jn/107.10.1816.
Pregnant rats and rabbits were given excess vitamin A, in the form of retinyl acetate or retinoic acid, for the 3-day period just prior to palatal closure in the fetuses. Twenty-four hours later, the various forms of vitamin A, and their levels, were determined in fetal liver and carcass and in maternal liver and serum by thin-layer chromatography. The predominant forms of vitamin A found in both fetal and maternal tissues were retinyl palmitate, retinol and retinoic acid. In both species, the tissues from the groups treated with retinoic acid contained levels of vitamin A similar to those found in control tissues. After retinyl acetate treatment in the rat, both of the maternal tissues studied had elevated vitamin A, whereas in the rabbit only maternal liver levels increased. In the groups treated with retinyl acetate, the ratio of the vitamin A levels in fetal liver: maternal serum reflected a species difference: the ratio was lower than the control value in the rabbit and higher than controls in the rat. Radiotracer studies in the rat, using either 3H-retinol or 14C-retinoic acid, demonstrated vitamin A transport across the placenta, with vitamin A concentrating in the fetal liver.
在胎儿腭部闭合前3天，给怀孕的大鼠和兔子过量服用醋酸视黄酯或视黄酸形式的维生素A。24小时后，通过薄层色谱法测定胎儿肝脏和尸体以及母体肝脏和血清中各种形式的维生素A及其含量。在胎儿和母体组织中发现的维生素A的主要形式是棕榈酸视黄酯、视黄醇和视黄酸。在这两个物种中，用视黄酸处理的组的组织中维生素A的含量与对照组织中的含量相似。在大鼠中用醋酸视黄酯处理后，所研究的两个母体组织中的维生素A含量均升高，而在兔子中只有母体肝脏中的含量增加。在用醋酸视黄酯处理的组中，胎儿肝脏中维生素A含量与母体血清中维生素A含量的比值反映了物种差异：该比值在兔子中低于对照值，在大鼠中高于对照值。在大鼠中使用³H-视黄醇或¹⁴C-视黄酸进行的放射性示踪研究表明，维生素A可穿过胎盘，并在胎儿肝脏中富集。
