Maes B D, Ghoos Y F, Geypens B J, Hiele M I, Rutgeerts P J
Department of Medicine, University Hospital Gasthuisberg, Leuven, Belgium.
Gut. 1996 Jan;38(1):23-7. doi: 10.1136/gut.38.1.23.
The variable gastric emptying rate of a test meal is one of the major problems in evaluating accurately gastrointestinal physiological functions beyond the stomach. The aim of this study was to evaluate the effect of the gastric emptying rate on the rate of intraluminal lipolysis. Thirty four subjects without pancreatic disease (21 with a normal gastric emptying and 13 with a known slow gastric emptying) and 14 subjects with pancreatic disease (four without and 10 with pancreatic insufficiency) were studied using a dual labelled breath test. The test meal consisted of one egg, 60 grams of white bread, 10 grams of margarine, and 150 ml of water (350 kcal). The egg yolk was labelled with 91 mg of 13C-octanoic acid, the margarine was labelled with 296 kBq of distearyl-2-14C-octanoyl-glycerol. Breath samples were taken every 15 minutes during six hours and analysed for 13CO2 and 14CO2 content. The gastric emptying rate of the meal was evaluated by the gastric emptying coefficient, the half emptying time, and the lag phase; the rate of intraluminal lipolysis was evaluated by the six hours cumulative 14CO2 excretion. Despite a clear distinction in the rate of intraluminal lipolysis, no difference could be detected in gastric emptying rate of the test meal between subjects without and with pancreatic disease. In subjects with pancreatic insufficiency, intraluminal hydrolysis was the rate limiting process in fat assimilation; in patients without pancreatic insufficiency, however, gastric emptying could be rate limiting. Therefore, patients with known slow gastric emptying, displayed a significantly decreased rate of intraluminal lipolysis compared with normal controls. This decrease could be corrected for accurately using a correction factor based on the gastric emptying coefficient. In conclusion, the combined 13C-octanoic acid and 14C-mixed triglyceride breath test permits the measurement of gastric emptying rate and intraluminal lipolysis simultaneously in a minimally invasive way. Correction of intraluminal lipolysis rate for gastric emptying rate of the given test meal permits evaluation of fat assimilation rates in a physiological way regardless of gastric emptying disorders.
试餐的胃排空速率可变是准确评估胃以外胃肠道生理功能的主要问题之一。本研究的目的是评估胃排空速率对腔内脂肪分解速率的影响。使用双标记呼气试验对34名无胰腺疾病的受试者（21名胃排空正常，13名已知胃排空缓慢）和14名胰腺疾病受试者（4名无胰腺功能不全，10名有胰腺功能不全）进行了研究。试餐包括一个鸡蛋、60克白面包、10克人造黄油和150毫升水（350千卡）。蛋黄用91毫克13C-辛酸标记，人造黄油用296千贝克勒尔的二硬脂酰-2-14C-辛酰甘油标记。在6小时内每隔15分钟采集呼气样本，并分析其中13CO2和14CO2的含量。通过胃排空系数、半排空时间和延迟期评估试餐的胃排空速率；通过6小时累积14CO2排泄量评估腔内脂肪分解速率。尽管腔内脂肪分解速率有明显差异，但在无胰腺疾病和有胰腺疾病的受试者之间，试餐的胃排空速率未检测到差异。在有胰腺功能不全的受试者中，腔内水解是脂肪同化的限速过程；然而，在无胰腺功能不全的患者中，胃排空可能是限速因素。因此，已知胃排空缓慢的患者与正常对照组相比，腔内脂肪分解速率显著降低。使用基于胃排空系数的校正因子可以准确校正这种降低。总之，13C-辛酸和14C-混合甘油三酯联合呼气试验能够以微创方式同时测量胃排空速率和腔内脂肪分解。根据给定试餐的胃排空速率校正腔内脂肪分解速率，无论胃排空障碍如何，都能以生理方式评估脂肪同化率。
