Absorption of oleic and palmitic acids from emulsions and micellar solutions.
Absorption of oleic and palmitic acids from emulsions and micellar solutions.
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从乳液和胶束溶液中吸收油酸和棕榈酸。
DOI：
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发表时间：
1968
影响因子：
15.9
通讯作者：
R. L. Willix
中科院分区：
文献类型：
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作者：
W. Simmonds;T. Redgrave;R. L. Willix
将脂类混合物(单油酸、油酸-1-(14)C和棕榈酸-9，10-(3)H)以稳定的速度注入禁食未麻醉的大鼠十二指肠内8小时。给予相同剂量的脂质和纯结合胆盐，作为乳剂，2.5 mM胆盐，或胶束溶液，10 mM胆盐。该乳剂含有极少的胶束脂或不含胶束脂。收集胸管淋巴，在一些实验中，胆汁和胰液被引流到外部。输注4-5小时后，乳剂和胶束溶液可获得与胶束溶液相同的稳定淋巴输出。结果表明，在几乎没有胶束增溶的情况下，脂肪酸的吸收是有效的。在胆瘘加胰瘘的大鼠中，标记的甘油三酯在相同的乳化颗粒中相对于游离脂肪酸的吸收较差。这表明脂肪酸是以单分子溶液的形式转移到吸收细胞中的，而不是以乳状液的形式。用合成的非离子洗涤剂代替胆汁混合物中的胆盐，给胆瘘和胰瘘的大鼠服用，并不影响放射性脂肪酸的淋巴输出。这表明，在没有胆盐的情况下，标记的游离脂肪酸的粘膜酯化是正常的。脂质的物理状态不影响吸收途径。最后，将淋巴中酯化脂肪产量的增加与标记脂肪的产量进行比较，表明脂肪吸收对内源性未标记脂肪的周转没有太大影响。结果与内源性淋巴脂肪主要来源于胆汁再吸收的观点一致。
A lipid mixture (monoolein, oleic acid-1-(14)C, and palmitic acid-9,10-(3)H) was infused intraduodenally at a steady rate for 8 hr in fasted, unanesthetized rats. The same dose of lipid was given together with pure conjugated bile salts either as an emulsion, 2.5 mM bile salts, or as a micellar solution, 10 mM bile salts. The emulsion contained very little or no micellar lipid. Thoracic duct lymph was collected and in some experiments bile and pancreatic juice were drained to the exterior. After 4-5 hr infusion the same steady lymphatic output of radioactive fatty acids was obtained with emulsion as with micellar solution. It was concluded that absorption of fatty acid could proceed efficiently in the virtual absence of micellar solubilization. In rats with biliary plus pancreatic fistulae, labeled triglyceride was absorbed poorly relative to free fatty acids in the same emulsified particles. This suggested that fatty acids were transferred to the absorptive cells in monomolecular solution and not as emulsion particles. Substitution of a synthetic nonionic detergent for bile salts in lipid mixtures given to rats with biliary and pancreatic fistulae did not affect the lymphatic output of radioactive fatty acids. This indicated that mucosal esterification of labeled free fatty acids was normal in the absence of bile salts. The physical state of the lipid did not affect the pathway of absorption. Finally, comparison of the increased output of esterified fat in the lymph with the output of labeled fat suggested that fat absorption did not greatly affect the turnover of endogenous, unlabeled fat. Results were consistent with the view that most of the endogenous lymph fat comes from reabsorbed biliary lipid.