METABOLISM OF GLUTAMINE IN NEWBORN INFANTS

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。适当的营养补充对于早产儿和患病婴儿的管理和护理至关重要。建议在补充配方中加入谷氨酰胺，因为它可以降低发病率并帮助极低出生体重的婴儿适应子宫外环境。本研究旨在研究补充谷氨酰胺对正常健康足月婴儿出生后（24-48小时）或3-4周龄期间蛋白质损失和蛋白质转化的代谢影响。假设：1)出生后立即补充谷氨酰胺会降低谷氨酰胺的合成和利用，而尿素产量会增加；2)出生后补充葡萄糖和氨基酸不会立即影响新陈代谢；3)出生后，支链氨基酸的转氨率高；4)在3-4周龄时，补充葡萄糖和氨基酸可促进蛋白质的增加。这是一个相对小规模的试验，试图在组间设计中招募4组正常婴儿（每组N= 15）。将使用稳定同位素输注亮氨酸、苯丙氨酸、尿素、谷氨酰胺和碳酸氢钠来评估蛋白质和氨基酸的周转。此外，呼吸样本将被获取以测量氧化速率。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Appropriate nutritional supplementation is essential in the management and care of premature and sick infants. It is recommended that glutamine be included in the supplement formula because it may reduce morbidity and help very low birth weight infants adapt to the extrauterine environment. The present study proposes to examine the metabolic effects of glutamine supplementation on protein loss and protein turnover in normal, healthy term infants in the periods immediately after birth (24-48 hours) or at 3-4 weeks of age. It is hypothesized that: 1) glutamine synthesis and utilization will be reduced and that urea production will be increased during supplementation immediately after birth; 2) glucose and amino acid supplementation will not impact metabolism immediately after birth; 3) transamination of branched amino acids will be high immediately after birth; 4) glucose and amino acid supplementation enhance protein accretion at 3-4 weeks of age. This is a relatively small-scale trial that seeks to enroll 4 groups (N= 15 per group) of normal infants in a between group design. Protein and amino acid turnover will be assessed using stable isotope infusions of leucine, phenylalanine, urea, glutamine and bicarbonate sodium. In addition, breath samples will be obtained to measure oxidation rates.