Morlese J F, Forrester T, Del Rosario M, Frazer M, Jahoor F
U.S. Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.
J Nutr. 1997 Aug;127(8):1469-74. doi: 10.1093/jn/127.8.1469.
This study was undertaken to determine the following: 1) the kinetic changes responsible for the depletion and repletion of plasma transferrin (Tr) concentration in children with protein-energy malnutrition (PEM); 2) the role of infection in mediating these changes; and 3) whether plasma Tr concentration is related to body protein status. We measured plasma Tr concentration, and fractional (FSR) and absolute (ASR) Tr synthesis rates with the use of a constant intragastric infusion of 2H3-leucine in 14 children with PEM, at 2 d postadmission (study 1), 8 d postadmission when infections were under control (study 2), and at recovery (study 3). In studies 1 and 2, the children synthesized less Tr and had lower Tr concentrations compared with values at recovery. When infections were controlled, plasma Tr concentration rose, but Tr synthesis was unchanged. There were only fair correlations (P < 0. 05) between plasma Tr concentrations and indices of wasting. Concerning malnourished children, we reached the following conclusions: 1) changes in the Tr pool size are achieved mainly through changes in synthesis rate; 2) infections play a minor role in reducing the Tr pool through either changes in the rate of catabolism or loss from the intravascular space; and 3) Tr concentration is not a very good indicator of protein nutritional status.
1）蛋白质 - 能量营养不良（PEM）患儿血浆转铁蛋白（Tr）浓度消耗和补充所涉及的动力学变化；2）感染在介导这些变化中所起的作用；3）血浆Tr浓度是否与机体蛋白质状态相关。我们对14名PEM患儿在入院后2天（研究1）、感染得到控制的入院后8天（研究2）以及恢复时（研究3），通过持续胃内输注2H3 - 亮氨酸来测量血浆Tr浓度、Tr的分数合成率（FSR）和绝对合成率（ASR）。在研究1和2中，与恢复时的值相比，患儿合成的Tr较少且Tr浓度较低。当感染得到控制时，血浆Tr浓度升高，但Tr合成未改变。血浆Tr浓度与消瘦指标之间仅有中等程度的相关性（P < 0.05）。关于营养不良患儿，我们得出以下结论：1）Tr池大小的变化主要通过合成率的变化实现；2）感染在通过分解代谢率的变化或血管内空间的丢失来减少Tr池方面起次要作用；3）Tr浓度不是蛋白质营养状况的一个很好指标。
