Simmonds W J, Redgrave T G, Willix R L
J Clin Invest. 1968 May;47(5):1015-25. doi: 10.1172/JCI105791.
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.
将一种脂质混合物（单油酸甘油酯、油酸 -1-(14)C 和棕榈酸 -9,10-(3)H）以稳定速率经十二指肠内注入禁食、未麻醉的大鼠体内，持续 8 小时。给予相同剂量的脂质，同时加入纯的结合胆汁盐，分别制成乳剂（2.5 mM 胆汁盐）或胶束溶液（10 mM 胆汁盐）。乳剂中几乎不含或不含胶束脂质。收集胸导管淋巴液，在一些实验中，将胆汁和胰液引流至体外。输注 4 - 5 小时后，乳剂和胶束溶液产生的放射性脂肪酸淋巴输出量相同。得出的结论是，在几乎不存在胶束增溶作用的情况下，脂肪酸的吸收仍能高效进行。在患有胆管加胰管瘘的大鼠中，相对于相同乳化颗粒中的游离脂肪酸，标记的甘油三酯吸收较差。这表明脂肪酸是以单分子溶液形式而非乳剂颗粒形式转移至吸收细胞的。用合成非离子洗涤剂替代患有胆管和胰管瘘的大鼠所给予脂质混合物中的胆汁盐，并不影响放射性脂肪酸的淋巴输出量。这表明在没有胆汁盐的情况下，标记游离脂肪酸的黏膜酯化是正常的。脂质的物理状态不影响吸收途径。最后，将淋巴中酯化脂肪的增加输出量与标记脂肪的输出量进行比较，结果表明脂肪吸收对内源性未标记脂肪的周转影响不大。结果与以下观点一致，即大部分内源性淋巴脂肪来自重新吸收的胆汁脂质。
