Sulkers E J, Lafeber H N, van Goudoever J B, Kalhan S C, Beaufrère B, Sauer P J
Erasmus University and Academic Hospital/Sophia Children's Hospital, Rotterdam, The Netherlands.
Pediatr Res. 1993 Feb;33(2):101-5. doi: 10.1203/00006450-199302000-00002.
Several formulas for preterm infants contain medium-chain triglycerides (MCT) to enhance fat absorption. Although fat absorption with MCT was slightly higher in several studies in preterm infants, a beneficial effect on growth has only been reported in one publication. We hypothesized that when part of the fat blend of preterm formula is substituted by MCT oil, this might lead to a different metabolic pattern in which, due to the preferential oxidation of MCT, an increase in lipogenesis from glucose could lead to an increase in metabolic rate. To study the impact of MCT on glucose metabolism, 18 preterm infants were randomized to receive either an MCT or an LCT formula containing 38- and 6%-by-weight medium-chain fatty acids, respectively, in their fat blend. At 4 wk of age, the metabolic rate, substrate utilization, glucose kinetics, and oxidation were measured by indirect respiratory calorimetry in combination with a constant-rate oral infusion of [U-13C]glucose. The "true" rate of appearance of glucose (Ra "true") was measured from the dilution of the uniformly labeled (m + 6) species of infused tracer, whereas "apparent" rate of appearance of glucose (Ra "apparent") was measured from the dilution of infused tracer C (carbon). The latter was measured by an on-line combustion method using a gas chromatograph-isotope ratio mass spectrometer. At a carbohydrate intake of 8.4 mg.kg-1.min-1, total utilization of carbohydrate was equal in both groups at 7.6 mg.kg-1.min-1.(ABSTRACT TRUNCATED AT 250 WORDS)
几种早产儿配方奶粉含有中链甘油三酯（MCT）以提高脂肪吸收。尽管在几项针对早产儿的研究中，含MCT的脂肪吸收略高，但只有一篇出版物报道了其对生长的有益作用。我们推测，当早产儿配方奶粉中的部分脂肪混合物被MCT油替代时，这可能会导致不同的代谢模式，其中由于MCT的优先氧化，葡萄糖生成脂肪的增加可能会导致代谢率升高。为了研究MCT对葡萄糖代谢的影响，18名早产儿被随机分组，分别接受脂肪混合物中分别含有38%和6%（按重量计）中链脂肪酸的MCT或LCT配方奶粉。在4周龄时，通过间接呼吸热量测定法结合恒速口服输注[U-13C]葡萄糖来测量代谢率、底物利用、葡萄糖动力学和氧化。葡萄糖的“真实”出现率（Ra“真实”）通过输注示踪剂均匀标记的（m+6）物种的稀释来测量，而葡萄糖的“表观”出现率（Ra“表观”）通过输注示踪剂C（碳）的稀释来测量。后者通过使用气相色谱-同位素比质谱仪的在线燃烧法测量。在碳水化合物摄入量为8.4mg·kg-1·min-1时，两组的碳水化合物总利用率均为7.6mg·kg-1·min-1。（摘要截断于250字）
