Fernández E, Borgström B
Department of Physiological Chemistry, University of Lund, Sweden.
Lipids. 1990 Sep;25(9):549-52. doi: 10.1007/BF02537163.
The aim of the present study was to characterize the intestinal absorption of retinol and retinyl palmitate in thoracic duct and bile duct fistulated rats and to investigate the effect of a simultaneously administered lipase inhibitor, tetrahydrolipstatin (THL). Absorption was determined as lymphatic recovery over a 24-hr period, including an initial 12-hr continuous intraduodenal infusion of either [11,12-3H]retinol or [11,12-3H]retinyl palmitate given in emulsified glyceryl trioleate or in mixed micellar solution of monoolein and oleic acid. From micellar dispersion, labeled retinol and retinyl palmitate were recovered in the lymph to 50-60% and both to the same extent. Administered in emulsified form, labeled retinol from fed retinyl palmitate was recovered to 47%, but retinol from fed retinol to only 18%. THL (10(-4) M) in the infusate had no significant effect on the recovery of 14C-labeled oleic acid. The recovery of label from emulsified glyceryl tri[1-14C]oleate was significantly decreased at this concentration of THL (76.5% vs 19.6% recovery). When administered in emulsified form, retinol absorption was not significantly affected by THL at 10(-4) M, while retinyl palmitate absorption was very significantly decreased (5.0% compared to 47.8%). In the presence of THL, retinol absorption from retinyl palmitate in micellar solution was decreased (from 58% to 17%). Most of the retinol in the lymph extracts (72.2 to 91.3) was present as retinyl ester, regardless of the chemical and physical form of administration. Furthermore, THL did not induce any change in this pattern.
本研究的目的是描述胸导管和胆管造瘘大鼠中视黄醇和棕榈酸视黄酯的肠道吸收情况，并研究同时给予的脂肪酶抑制剂四氢脂抑素（THL）的作用。吸收情况通过24小时内的淋巴回收量来确定，包括最初12小时在十二指肠内持续输注以乳化三油酸甘油酯形式或单油酸甘油酯与油酸混合胶束溶液形式给予的[11,12-³H]视黄醇或[11,12-³H]棕榈酸视黄酯。从胶束分散液中，标记的视黄醇和棕榈酸视黄酯在淋巴中的回收率为50%-60%，两者回收率相同。以乳化形式给予时，来自喂食棕榈酸视黄酯的标记视黄醇回收率为47%，但来自喂食视黄醇的视黄醇回收率仅为18%。输注液中的THL（10⁻⁴M）对¹⁴C标记油酸的回收率没有显著影响。在此THL浓度下，乳化三[1-¹⁴C]油酸甘油酯的标记回收率显著降低（76.5%对19.6%的回收率）。以乳化形式给予时，10⁻⁴M的THL对视黄醇吸收没有显著影响，而棕榈酸视黄酯吸收则非常显著地降低（5.0%对47.8%）。在THL存在的情况下，胶束溶液中棕榈酸视黄酯的视黄醇吸收降低（从58%降至17%）。无论给药的化学和物理形式如何，淋巴提取物中的大部分视黄醇（72.2%至91.3%）以视黄酯形式存在。此外，THL并未引起这种模式的任何变化。
