Williams N S, Meyer J H, Jehn D, Miller J, Fink A S
Gastroenterology. 1984 Jun;86(6):1451-9.
Using conscious dogs with chronic gastrointestinal fistulas, we studied the intestinal transit of radiolabeled liver particles relative to the transit of a liquid phase marker, polyethylene glycol. All studies were performed during a "fed" intestinal motility pattern induced by feeding or by intestinal perfusion with a fat-containing solution. Median transit times were determined from duodenum to fistulas at the midintestine, or at the terminal ileum, by recovery of polyethylene glycol and radiolabel in effluent from the fistulas. We also sized recovered particles of liver to determine the extent of digestion or fragmentation, or both, in transit. After a steak meal, when liquid flows were very low, the liquid marker and small (0.5-0.7 mm) and large (2-3 mm) particles moved through the proximal intestine together at a slow rate. When intestinal liquid flows were progressively increased from 2 to 24 ml/min by intestinal perfusion, transit was progressively accelerated; but 2-mm particles moved at 25%-20% of the rate of polyethylene glycol or 0.5-mm particles. Increasing transit with increasing flows was associated with decreasing digestion or fragmentation of liver particles. Under most conditions, 2-mm particles were well digested or fragmented than 0.5-mm particles. We conclude that fluid flows have a major effect on transit and digestion of food particles in the small intestine.
我们使用患有慢性胃肠瘘的清醒犬，研究了放射性标记的肝颗粒相对于液相标记物聚乙二醇的肠道转运情况。所有研究均在通过喂食或用含脂肪溶液进行肠道灌注诱导的“进食”肠道运动模式下进行。通过从瘘管流出物中回收聚乙二醇和放射性标记物，确定从十二指肠到中肠瘘管或回肠末端的中位转运时间。我们还对回收的肝颗粒进行了大小测定，以确定转运过程中消化或破碎的程度，或两者兼有。进食牛排后，当液体流量非常低时，液体标记物以及小颗粒（0.5 - 0.7毫米）和大颗粒（2 - 3毫米）以缓慢的速度一起通过近端肠道。当通过肠道灌注使肠道液体流量从2毫升/分钟逐渐增加到24毫升/分钟时，转运逐渐加速；但2毫米颗粒的移动速度仅为聚乙二醇或0.5毫米颗粒的25% - 20%。转运随流量增加而加快与肝颗粒消化或破碎程度降低有关。在大多数情况下，2毫米颗粒比0.5毫米颗粒消化或破碎得更好。我们得出结论，液体流量对小肠中食物颗粒的转运和消化有主要影响。
