Kudo Y, Boyd C A
Department of Human Anatomy, Oxford University, UK.
J Inherit Metab Dis. 1990;13(4):617-26. doi: 10.1007/BF01799516.
Brush border and basal plasma membrane vesicles prepared from normal term human placental syncytiotrophoblast have been used to study amino acid transport. Such studies are reviewed and novel results presented which confirm that saturation of placental transport by phenylalanine is unlikely to limit delivery of this amino acid to the fetus even with grossly raised maternal concentrations. Such raised maternal levels of phenylalanine are, however, likely to severely embarrass the delivery to the fetus across the placental brush border membrane of L-tyrosine and, to a lesser extent, of L-tryptophan. Reasons for thinking that this may be relevant to the fetal damage found in maternal PKU are discussed.
从足月正常人类胎盘合体滋养层制备的刷状缘和基底质膜囊泡已被用于研究氨基酸转运。本文综述了此类研究，并呈现了新的结果，这些结果证实，即使母体浓度大幅升高，苯丙氨酸对胎盘转运的饱和也不太可能限制该氨基酸向胎儿的输送。然而，母体苯丙氨酸水平的这种升高可能会严重妨碍L-酪氨酸以及程度较轻的L-色氨酸通过胎盘刷状缘膜向胎儿的输送。文中讨论了认为这可能与母体苯丙酮尿症中发现的胎儿损伤相关的原因。
