Lemons J A, Reyman D, Schreiner R L
J Pediatr Gastroenterol Nutr. 1984 Mar;3(2):249-55. doi: 10.1097/00005176-198403000-00015.
The present investigation was undertaken to quantitate the whole-blood amino acid concentrations of the mother and fetus over an extended period of fasting using a chronic sheep preparation. Fetal amino acid levels generally increased or remained relatively high during the fast (e.g., alanine, glycine, valine, leucine). In contrast to the situation in the fetus, most amino acids (alanine, glycine, glutamine, serine, and threonine) decreased in concentration in the ewe with fasting. Alanine levels changed most dramatically in the ewe, decreasing to less than 50% of the fed state values within 72 h of fasting. Therefore, while the supply of gluconeogenic amino acids becomes limited within the maternal circulation during fasting, levels of these amino acids remain high or increase in the fetal arterial blood.
本研究旨在使用慢性绵羊制备模型，对长时间禁食期间母羊和胎儿的全血氨基酸浓度进行定量分析。在禁食期间，胎儿的氨基酸水平通常会升高或保持相对较高水平（例如丙氨酸、甘氨酸、缬氨酸、亮氨酸）。与胎儿的情况相反，随着禁食时间延长，母羊体内大多数氨基酸（丙氨酸、甘氨酸、谷氨酰胺、丝氨酸和苏氨酸）的浓度下降。母羊体内丙氨酸水平变化最为显著，禁食72小时内降至进食状态值的50%以下。因此，虽然禁食期间母体循环中糖异生氨基酸的供应变得有限，但这些氨基酸在胎儿动脉血中的水平仍然很高或有所增加。
