Williams J B, Pramanik B C, Napoli J L
J Lipid Res. 1984 Jun;25(6):638-45.
High-performance liquid chromatography systems were developed to rapidly separate retinol from its esters, analyze the total spectrum of neutral vitamin A compounds, and purify retinyl esters to homogeneity. Chemical ionization mass spectrometric techniques were used to identify vitamin A compounds; these techniques are also applicable to quantification of tissue vitamin A compounds. These methods provide rapid and sensitive techniques for separation and quantification of neutral retinol metabolites. Their utility was demonstrated by analysis of vitamin A metabolites in rat tissues under steady-state conditions. Tissue specificity was noted for the concentrations of retinol and its long-chain fatty acid esters, the ratio of retinol to retinyl esters, and the fatty acid composition of retinyl esters. Quantitatively minor amounts of several neutral polar retinol metabolites were detected, but neither 13-cis-retinol nor 4-hydroxyretinol was observed in vivo as metabolites of retinol in kidney.
高效液相色谱系统的开发旨在快速分离视黄醇及其酯类，分析中性维生素A化合物的全谱，并将视黄酯纯化至同质。化学电离质谱技术用于鉴定维生素A化合物；这些技术也适用于组织中维生素A化合物的定量分析。这些方法为中性视黄醇代谢物的分离和定量提供了快速且灵敏的技术。通过在稳态条件下分析大鼠组织中的维生素A代谢物，证明了它们的实用性。视黄醇及其长链脂肪酸酯的浓度、视黄醇与视黄酯的比例以及视黄酯的脂肪酸组成具有组织特异性。检测到了几种中性极性视黄醇代谢物的定量微量，但在肾脏中未观察到13-顺式视黄醇和4-羟基视黄醇作为视黄醇的体内代谢物。
