Effect of Intravenous Amino Acids on Protein Metabolism of Preterm Infants during the First Three Days of Life
Effect of Intravenous Amino Acids on Protein Metabolism of Preterm Infants during the First Three Days of Life
复制标题
静脉注射氨基酸对早产儿出生后三天蛋白质代谢的影响
作者：
A. Rivera;E. Bell;D. Bier
摘要：将23例呼吸窘迫综合征早产儿（平均出生体重1.07 kg, SD 0.24 kg）随机分为两组，分别在出生后第1天开始静脉注射葡萄糖或葡萄糖加氨基酸（1.5 g·kg−1·d−1）。血氨和血清尿素、CO2含量、钠、钾、氯化物和离子钙浓度均正常，治疗组间无差异。氨基酸组氮平衡显著增加[88 （SD 54）对- 135 (SD 45) mg·kg - 1 d - 1]。在12名婴儿（7名，仅葡萄糖；5名，葡萄糖和氨基酸）中，亮氨酸动力学研究也在生命的第3天进行。这12名婴儿接受了持续4小时的L-[1-13C]亮氨酸灌注。采集血液和呼气分别分析[1-13C]酮异己酸酯和13CO2。计算亮氨酸周转率和氧化率。氨基酸组的亮氨酸转化率和氧化率均显著高于葡萄糖组[分别为241 （SD 38）对164 (SD 25) μmol·kg−1·h−1和71 （SD 22）对40 (SD 17) μmol·kg−1·h−1]。此外，氨基酸组的蛋白质合成计算率更高[6.9 (SD 1.1) vs 5.0 (SD 1.2) g·kg−1·d−1]。这些数据表明，从出生第1天开始，给患病早产儿静脉注射氨基酸（1.5 g·kg - 1·d - 1），由于蛋白质合成增加，可以改善全身蛋白质平衡。
ABSTRACT: Twenty-three preterm infants with respiratory distress syndrome (mean birth weight 1.07 kg, SD 0.24 kg) were randomly assigned to receive glucose alone or glucose with amino acids (1.5 g·kg−1·d−1) i.v. beginning on the 1st d of life. Blood ammonia and serum urea, CO2 content, sodium, potassium, chloride, and ionized calcium concentrations were normal and did not differ between treatment groups. Nitrogen balance was significantly greater in the group that received amino acids [88 (SD 54) versus −135 (SD 45) mg·kg−1 d−1]. In 12 infants (seven, glucose-only; five, glucose and amino acids), leucine kinetic studies were also performed on the 3rd d of life. These 12 infants received a 4-h primed constant infusion of L-[1-13C] leucine. Blood and breath were collected and analyzed for [1-13C]ketoisocaproate and 13CO2, respectively. Leucine turnover and oxidation were calculated. Both leucine turnover and oxidation were significantly higher in the group receiving amino acids than in the glucose-only group [241 (SD 38) versus 164 (SD 25) μmol·kg−1·h−1 and 71 (SD 22) versus 40 (SD 17) μmol·kg−1·h−1, respectively]. In addition, the calculated rate of protein synthesis was higher in the group receiving amino acids [6.9 (SD 1.1) versus 5.0 (SD 1.2) g·kg−1·d−1]. These data indicate that the i.v. administration of amino acids (1.5 g·kg−1·d−1) to ill preterm infants beginning on the 1st d of life improves whole-body protein balance as a result of increased protein synthesis.