De Gaetano A, Castagneto M, Mingrone G, Gangeri G, Sganga G, Tataranni P A, Raguso C, Greco A V
CNR-Centro Fisiopatologia Shock, Università Cattolica del Sacro Cuore, Facoltà di Medicina e Chirurgia A. Gemelli, Rome, Italy.
JPEN J Parenter Enteral Nutr. 1994 Mar-Apr;18(2):134-40. doi: 10.1177/0148607194018002134.
To determine the hydrolysis rate of medium-chain triglycerides (MCTs) to medium-chain free fatty acids (MCFAs) and the disposition rate of MCFAs, five healthy volunteers (H) and eight surgically stressed patients (S) received 0.5 mL of Lipofundin 20% per kilogram body weight as an intravenous bolus. Serum MCTs (C8 and C10) and MCFAs were measured by high-performance liquid chromatography during the 120 minutes postinjection. A linear two-compartment model was found to be descriptive and robust: the apparent volumes of distribution were found to be similar in healthy and surgical subjects for both MCTs and MCFAs. The first-order transformation rate constant (hydrolysis) from MCTs to MCFAs was not significantly different between the H and S groups (overall 0.112 +/- 0.022/min, C8; 0.078 +/- 0.020/min, C10). The rate constant for tissue MCFA uptake from plasma was significantly different between S and H subjects both for C10 alone (H: 0.0337 +/- 0.0078; S: 0.1194 +/- 0.0240; p = .020) and for C8 and C10 together (H: 0.0382 +/- 0.0054; S: 0.1012 +/- 0.0168; p = .008), whereas it failed to attain significance when C8 alone was considered (H: 0.047 +/- 0.0077; S: 0.0829 +/- 0.0230; p = .210). These results show that use of MCTs is increased in surgical patients because of enhanced tissue uptake of the corresponding free fatty acids, whereas there does not seem to be an increase of MCT hydrolysis in response to acute disease. This would indicate that the stressed patient is in fact able to effectively use this alternative lipid substrate in the face of increased metabolic demand.
为了确定中链甘油三酯（MCTs）水解为中链游离脂肪酸（MCFAs）的速率以及MCFAs的处置速率，五名健康志愿者（H）和八名手术应激患者（S）以每千克体重静脉推注0.5 mL 20%的Lipofundin。在注射后120分钟内，通过高效液相色谱法测定血清MCTs（C8和C10）和MCFAs。发现线性二室模型具有描述性且稳健：对于MCTs和MCFAs，健康受试者和手术受试者的表观分布容积相似。H组和S组之间从MCTs到MCFAs的一级转化速率常数（水解）无显著差异（总体上，C8为0.112±0.022/分钟；C10为0.078±0.020/分钟）。仅C10时以及C8和C10一起时，血浆中MCFA被组织摄取的速率常数在S组和H组受试者之间存在显著差异（仅C10时，H：0.0337±0.0078；S：0.1194±0.0240；p = 0.020；C8和C10一起时，H：0.0382±0.0054；S：0.1012±0.0168；p = 0.008）；而仅考虑C8时未达到显著性（H：0.047±0.0077；S：0.0829±0.0230；p = 0.210）。这些结果表明，由于相应游离脂肪酸的组织摄取增强，手术患者中MCTs的使用增加，而急性疾病似乎并未导致MCT水解增加。这表明应激患者实际上能够在代谢需求增加的情况下有效利用这种替代脂质底物。
