Birth and adaptation to extrauterine life involve major shifts in the protein and energy metabolism of the human newborn. These include a shift from a state of continuous supply of nutrients including amino acids from the mother to cyclic periodic oral intake, a change in the redox state of organs, thermogenesis, and a significant change in the mobilization and use of oxidative substrates. The development of safe, stable isotopic tracer methods has allowed the study of protein and amino acid metabolism not only in the healthy newborn but also in those born prematurely and of low birth weight. These studies have identified the unique and quantitative aspects of amino acid/protein metabolism in the neonate, thus contributing to rational nutritional care of these babies. The present review summarizes the contemporary data on some of the significant developments in essential and dispensable amino acids and their relationship to overall protein metabolism. Specifically, the recent data of kinetics of leucine, phenylalanine, glutamine, sulfur amino acid, and threonine and their relation to whole-body protein turnover are presented. Finally, the physiological rationale and the impact of nutrient (amino acids) interventions on the dynamics of protein metabolism are discussed.

中文翻译：

---

人类新生儿中的蛋白质和氨基酸代谢。

出生和适应子宫外生活涉及人类新生儿蛋白质和能量代谢的重大转变。这些措施包括从母亲不断供应包括氨基酸在内的营养素到周期性的定期口服摄入，器官的氧化还原状态改变，生热作用以及氧化底物的动员和使用发生重大变化。安全，稳定的同位素示踪剂方法的发展不仅可以研究健康新生儿的蛋白质和氨基酸代谢，而且还可以研究早产和低出生体重的人的蛋白质和氨基酸代谢。这些研究已经确定了新生儿氨基酸/蛋白质代谢的独特和定量方面，从而有助于这些婴儿的合理营养护理。本综述总结了必需和可不需要氨基酸的一些重要进展及其与整体蛋白质代谢的关系的当代数据。具体而言，提供了亮氨酸，苯丙氨酸，谷氨酰胺，硫氨基酸和苏氨酸的动力学及其与全身蛋白质更新的关系的最新数据。最后，讨论了生理原理以及营养（氨基酸）干预对蛋白质代谢动力学的影响。