Influence of blood supply on lipid uptake from micellar solutions by the rat small intestine.
Influence of blood supply on lipid uptake from micellar solutions by the rat small intestine.
复制标题
血液供应对大鼠小肠从胶束溶液中摄取脂质的影响。
DOI：
10.1016/0005-2736(70)90177-x
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发表时间：
1970
期刊：
影响因子：
--
通讯作者：
C. Sylvén
中科院分区：
文献类型：
--
作者：
C. Sylvén
将含有微量不同放射性脂质的胶束溶液注射到大鼠的空肠段中，在两端结扎，有或没有血液供应。将溶液孵育不同时间，然后分离空肠组织并估计放射性摄取。在一个实验中，将空肠切片在胶束溶液中孵育不同的时间。在肠段血液供应完整的情况下，给药后0.5 h，不同脂质的摄取在8 - 30%之间。十八烷的摄取速率最快，其次是油酸、单油酸甘油酯和胆固醇。谷甾醇的摄取率约为胆固醇的三分之一。当段的血液供应中断时，所有脂质的摄取从1.5%下降到4.5%。5分钟后，随着时间的推移没有净摄取。胆固醇摄入量的下降幅度大于谷固醇摄入量。当含有KCN的胶束溶液注射到具有完整血液供应的空肠段中时，脂质摄取减少，类似于排除血液供应所产生的脂质摄取减少。与血供中断节段的低摄取相反，体外循环对放射性固醇的摄取随时间增加。谷甾醇的吸收程度与胆固醇相同。结果表明，肠道脂质吸收不能用传统的方法在体外研究。脂质从胶束渗透到粘膜上皮细胞被认为是一个主动过程，其排列被假设描述为四维膜。
A micellar solution containing trace amounts of different radioactive lipids was injected into the jejunal segment of a rat, tied off at both ends, with or without blood supply. The solution was incubated for different times after which the jejunal tissue was isolated and the uptake of radioactivity was estimated. In one experiment jejunal slices were incubated for different times in a micellar solution. With intact blood supply to the intestinal segment the uptake of the different lipids was between 8 and 30% 0.5 h after administration. Octadecane had the most rapid rate of uptake followed by oleic acid, monoolein and cholesterol. The rate of sitosterol uptake was about one-third that of cholesterol. When the blood supply to the segment was interrupted, the uptake decreased for all lipids to from 1.5 to 4.5%. After 5 min there was no net uptake with time. The cholesterol uptake decreased more than the sitosterol uptake. When a micellar solution containing KCN was injected into a jejunal segment with intact blood supply, there was a decrease in lipid uptake similar to that produced by exclusion of the blood supply. In contrast to the low uptake by segments with interrupted blood supply, the uptake of radioactive sterols by preparationsin vitroincreased with time. Sitosterol was taken up to the same extent as cholesterol. The results suggest that intestinal lipid absorption cannot be investigated by conventional methodsin vitro. The penetration of lipid from micelle to mucosa epithelial cell is thought to be an active process the arrangement of which is hypothetically described in a four-dimensional membrane.