METABOLISM AND CLINICAL APPLICATION OF OLIGOPEPTIDES

二十多年来，我们一直在调查各种 与寡肽同化有关的问题。 这些 研究包括二肽的转运和水解 及其氨基酸残基的代谢。 虽然我们的 研究已经产生了大量的新信息 对于寡肽，特别是二肽的代谢， 还有许多问题没有得到解答。 的目的 资助申请是提供这些问题的答案 完成了7个研究项目。 在第一个项目中， 将研究的消化和吸收功能的 肠粘膜和蛋白质代谢 二肽是人类膳食氮的唯一来源。 第二个项目，我们将研究肽的重要性， 蛋白餐后或肠内营养期间进入门静脉循环 狗的二肽营养。 在第三个项目中， 研究分子结构对同化的影响， 通过分离的肝脏、肌肉、肾脏、脑和红细胞， 大鼠 在第四个项目中，我们将研究 α-氨基氮和二肽的碳骨架， 连续静脉输注二肽。 在第五个项目中， 将研究饮食和激素变化对 二肽在大鼠肝脏、肌肉和肾脏中的代谢。 在 第六个项目，我们将调查是否恢复机构 蛋白质的患者通过肠外营养增强， 提供酪氨酸、谷氨酰胺和半胱氨酸作为甘氨酰- 二肽 由于溶解性或稳定性的问题， 胃肠外氨基酸溶液缺乏这些氨基酸。 在 第七个项目，我们将研究是否肽同化 肝脏，肌肉，肾脏和肠道在体内的狗会有所不同，如果 肽大小从2个增加到3个残基（三肽）。 上述研究的基础已在补助金中详细说明 应用程序. 广泛的技术，无论是由我们验证， 由其他调查员，建议调查每个 项目 我们相信，上述项目的完成， 将肽代谢领域充分推进到一个阶段， 这将允许肽在临床上广泛应用于 肠内和肠外营养的实践。 的重要性 肠内和肠外营养强调的事实是， 无法维持营养的患者不再需要 遭受营养不良的严重后果。

For over two decades we have been investigation various questions concerned with assimilation of oligopeptides. These investigations have included transport and hydrolysis of dipeptides and metabolism of their amino acid residues. Although our research has produced considerable amounts of new information on metabolism of oligopeptides, particularly dipeptides, there are still many questions that remain unanswered. The aim of this grant application is to provide answers to some of these questions by completing seven research projects. In the first project we will investigate the digestive and absorptive function of the intestinal mucosal membrane and protein metabolism when dipeptides are the sole source of dietary nitrogen in man. In the second project we will investigate the importance of peptide entry into portal circulation after a protein meal or during enteral nutrition with dipeptides in dogs. In the third project we will investigate the influence of molecular structure on assimilation of dipeptides by isolated liver, muscle, kidney, brain, and red cells in rats. In the fourth project we will investigate metabolism of the alpha-aminonitrogen and the carbon skeleton of dipeptides during continuous IV dipeptide infusion in rats. In the fifth project we will investigate the effects of dietary and hormonal alterations on metabolism of dipeptides by liver, muscle and kidney in rats. In the sixth project we will investigate whether restoration of body protein of patients by parenteral nutrition in enhanced by provision of tyrosine, glutamine, and cysteine as glycyl- dipeptides. Due to problems either in solubility or stability, parenteral amino acid solutions lack these amino acids. In the seventh project we will investigate whether peptide assimilation by liver, muscle, kidney and gut in vivo in dogs would differ if the size of peptide were increased from 2 to 3 residues (tripeptides). The basis for the above studies has been detailed in the grant application. A wide range of techniques, validated either by us or by other investigators, are proposed for investigation of each project. We believe that completion of the above projects will sufficiently advance the field of peptide metabolism to a stage which will allow a wide clinical application of peptides to the practice of enteral and parenteral nutrition. The importance of enteral and parenteral nutrition is underscored by the fact that patients who are unable to maintain their nutrition no longer need to suffer the serious consequences of malnutrition.