Holgate A M, Read N W
Dig Dis Sci. 1983 Sep;28(9):812-9. doi: 10.1007/BF01296904.
The times taken for a radiolabeled solid meal to empty from the stomach and terminal ileum and the absorption of the components of that meal were measured in 14 patients with terminal ileostomies under control conditions and after administration of either lactulose (40 g) or metoclopramide (20 mg tds), or magnesium sulfate (0.1 g/kg body weight). Absorption of each of the components of the meal was determined by chemical analysis of the ileostomy effluent. The radioisotope proved an excellent marker for the delivery of fat, protein, and carbohydrate residues. All three agents significantly reduced the time taken for the meal to empty from the ileum. This was associated with significant reductions in the absorption of fat, carbohydrate, protein, water, and electrolytes in the case of lactulose and magnesium sulfate. Although metoclopramide reduced transit time to the same degree as the other agents, its effect on absorption of fat, fluid, and electrolytes was much less, and absorption of protein and carbohydrate was unaffected. We therefore conclude that, although agents that accelerate postprandial transit of a meal may diminish absorption of the component of that meal in the small bowel, the extent to which this occurs cannot be predicted by a knowledge of transit kinetics alone and depends on the means by which transit is altered. The action of lactulose on the small intestine causes fluid and fat losses, sufficient to result in diarrhea and steatorrhea in a normal subject.
在对照条件下以及给予乳果糖（40克）、甲氧氯普胺（每日三次，每次20毫克）或硫酸镁（0.1克/千克体重）后，对14例回肠造口术患者进行了放射性标记固体餐从胃和回肠末端排空的时间以及该餐成分吸收情况的测量。通过对回肠造口流出物进行化学分析来确定餐中各成分的吸收情况。放射性同位素被证明是脂肪、蛋白质和碳水化合物残渣输送的极佳标志物。所有三种药物均显著缩短了餐从回肠排空的时间。对于乳果糖和硫酸镁而言，这与脂肪、碳水化合物、蛋白质、水和电解质的吸收显著减少有关。尽管甲氧氯普胺将转运时间缩短到了与其他药物相同的程度，但其对脂肪、液体和电解质吸收的影响要小得多，且对蛋白质和碳水化合物的吸收没有影响。因此，我们得出结论，尽管加速餐后餐食转运的药物可能会减少该餐食成分在小肠中的吸收，但仅通过了解转运动力学无法预测这种情况发生的程度，这取决于改变转运的方式。乳果糖对小肠的作用会导致液体和脂肪流失，足以使正常受试者出现腹泻和脂肪泻。
