Wilson D E, Chan I F, Ball M
Metabolism. 1983 May;32(5):514-7. doi: 10.1016/0026-0495(83)90016-1.
Retinyl esters have been thought to be carried solely by lipoproteins of intestinal origin (chylomicrons and their catabolic derivatives). Recent reports, however, have indicated that there may be significant transfer of retinyl esters from chylomicrons to low-density lipoproteins (LDL) in vitro, and that in other species, substantial amounts of retinyl esters may appear in LDL. Since in man lipoproteins of intestinal origin are not considered to contribute to a quantitatively significant extent to circulating LDL, we have examined this issue further. The distribution of retinol and retinyl esters within the plasma lipoproteins of eight normal human volunteers was measured following the ingestion of vitamin A along with a mixed meal. Retinyl esters appeared in the chylomicrons and very-low-density lipoproteins. Small amounts of retinyl esters were also detected in the intermediate- and low-density lipoprotein (LDL) classes. Estimates of the masses of retinyl esters, however, indicated that 5% or less of chylomicron retinyl esters appeared in the LDL. These observations are consistent with orderly chylomicron delipidation and provide further evidence that chylomicron-derived components do not contribute directly or to a quantitatively significant extent to circulating LDL.
视黄酯一直被认为仅由肠道来源的脂蛋白（乳糜微粒及其分解代谢衍生物）携带。然而，最近的报告表明，在体外视黄酯可能会从乳糜微粒大量转移至低密度脂蛋白（LDL），而且在其他物种中，大量视黄酯可能会出现在LDL中。由于在人类中，肠道来源的脂蛋白对循环LDL的定量贡献被认为不大，我们进一步研究了这个问题。在八名正常人类志愿者摄入维生素A并同时进食混合餐之后，测定了血浆脂蛋白中视黄醇和视黄酯的分布。视黄酯出现在乳糜微粒和极低密度脂蛋白中。在中密度脂蛋白和低密度脂蛋白（LDL）类别中也检测到少量视黄酯。然而，对视黄酯质量的估计表明，乳糜微粒视黄酯中只有5%或更少出现在LDL中。这些观察结果与乳糜微粒的有序脱脂一致，并进一步证明乳糜微粒衍生成分对循环LDL没有直接或定量上的显著贡献。
