Fenton E, Britton H G, Nixon D A
Biol Neonate. 1978;34(1-2):92-6. doi: 10.1159/000241111.
In situ placental perfusion has been used to study the role of the sheep placenta in fetal citrate metabolism. The perfusate citrate concentrations rose steadily to values higher than in fetal plasma. This rise was not influenced by intravenous administration of citrate to the ewe. Concentration and electropotential gradients indicate that transplacental passage is unlikely and the rise is probably due to placental synthesis. However, the quantity of citrate supplied to the fetus was calculated to be small compared with the fetal metabolic rate. Comparison with the guinea pig shows close similarity in fetal plasma concentrations and the amount of citrate formed per unit weight of fetus.
原位胎盘灌注已被用于研究绵羊胎盘在胎儿柠檬酸代谢中的作用。灌注液中柠檬酸浓度稳步上升，达到高于胎儿血浆中的值。这种上升不受向母羊静脉注射柠檬酸的影响。浓度和电位梯度表明，经胎盘转运不太可能，这种上升可能是由于胎盘合成。然而，与胎儿代谢率相比，供应给胎儿的柠檬酸量计算得出是很少的。与豚鼠相比，胎儿血浆浓度和每单位体重胎儿形成的柠檬酸量显示出密切的相似性。
