In vivo characteristics of placental amino acid transport and metabolism in ovine pregnancy - A review
In vivo characteristics of placental amino acid transport and metabolism in ovine pregnancy - A review
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DOI：
10.1053/plac.2002.0812
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发表时间：
2002-04-01
期刊：
影响因子：
3.8
通讯作者：
Battaglia, FC
中科院分区：
文献类型：
--
作者：
Battaglia, FC
在营养上重要的氨基酸的胎盘转运是进入胎儿循环的净进入率（脐吸收）。这种进入速率是跨细胞膜转运的函数，氨基酸之间竞争转运的作用，特别是跨滋养层的胎儿表面，以及它们在胎盘内的代谢和相互转化。这些不同的相互作用通量的结果是，母体浓度和胎儿供应的氨基酸之间的关系对于每种氨基酸不同。对于某些氨基酸，在胎盘的胎儿和母体表面都存在相对较大的双向通量。这些通量可以利用稳定同位素方法在体内测量。在胎盘和胎肝之间存在重要的器官间氨基酸交换。这种交换至少部分是胎儿肝脏中缺乏胎盘生成的功能。从胎儿肝脏释放的谷氨酸和丝氨酸都被胎盘从胎儿循环中摄取并在胎盘内代谢。(C)2002年IFPA和Elsevier Science Ltd.
The placental transport of amino acids which is nutritionally important is the net entry rate into the fetal circulation (the umbilical uptake). This entry rate is a function of transport across cell membranes, the effect of competition among amino acids for transport, particularly across the fetal surface of the trophoblast, and their metabolism and interconversion within the placenta. The result of these different interactive fluxes is that the relationship between maternal concentration and fetal supply of an amino acid differs for each amino acid. For some amino acids there are relatively large bidirectional fluxes at both the fetal and maternal surfaces of the placenta. These fluxes can be measured in vivo utilizing stable isotope methodology. There is an important interorgan exchange of amino acids between the placenta and fetal liver. This exchange is, at least in part, a function of the absence of gluconcogenesis in the fetal liver, Both glutamate and serine, which are released from the fetal liver, are taken up by the placenta from the fetal circulation and metabolized within the placenta. (C) 2002 IFPA and Elsevier Science Ltd.