Metges C C, Wolfram G
Nutrition Science Institute, Technical University of Munich, Freising-Weihenstephan, Germany.
J Nutr. 1991 Jan;121(1):31-6. doi: 10.1093/jn/121.1.31.
The special physical properties of medium-chain triglycerides (MCT) result in some substantial differences in their metabolism compared to that of long-chain triglycerides (LCT). Administering MCT is of importance in enteral nutrition of patients with disturbances of fat digestion or lipoprotein lipase deficiency. Their use in parenteral nutrition is also of interest. The purpose of this study was to compare the rate of conversion of MCT and LCT to CO2 after parenteral or oral administration in humans. At 1-wk intervals, a liquid formula diet (418 kJ/h for 8 h) was given to five healthy volunteers following an overnight fast. Two hours after starting this, they were given either 100 mg [13C]trioctanoate or [13C]trioleate orally or parenterally. Excess 13C in breath carbon dioxide was analyzed by mass-spectrometry, and oxidation rates over 7.5 h were calculated. Oxidation rates for [13C]trioctanoate were on the average 34.7% after enteral and 31.0% after parenteral administration, and for [13C]trioleate, 25.3 and 24.9%, respectively (p less than 0.05, trioctanoate vs. trioleate). The results show that the oxidation of trioctanoate in healthy humans is greater both after oral and parenteral administration and increases more rapidly than that of [13C]trioleate.
中链甘油三酯（MCT）的特殊物理性质导致其代谢与长链甘油三酯（LCT）相比存在一些显著差异。对于脂肪消化紊乱或脂蛋白脂肪酶缺乏的患者，给予MCT在肠内营养中具有重要意义。它们在肠外营养中的应用也备受关注。本研究的目的是比较在人体经肠内或肠外给予MCT和LCT后转化为二氧化碳的速率。在禁食过夜后，每隔1周给5名健康志愿者提供一种液体配方饮食（8小时内418 kJ/h）。开始这种饮食2小时后，给他们经口服或肠外给予100 mg [13C]三辛酸甘油酯或[13C]三油酸甘油酯。通过质谱分析呼出二氧化碳中过量的13C，并计算7.5小时内的氧化速率。[13C]三辛酸甘油酯经肠内给药后的氧化速率平均为34.7%，经肠外给药后的氧化速率平均为31.0%；[13C]三油酸甘油酯经肠内和肠外给药后的氧化速率分别为25.3%和24.9%（三辛酸甘油酯与三油酸甘油酯相比，p<0.05）。结果表明，在健康人体中，三辛酸甘油酯经口服和肠外给药后的氧化作用均更强，且比[13C]三油酸甘油酯增加得更快。
