Comparison of Intestinal Absorption and Esterification of 4-C 14 Vitamin D 3 and 4-C 14 Cholesterol in the Rat ∗

Summary

Intestinal absorption and esteri-fication of 4-C¹⁴ vitamin D₃ and 4-C¹⁴ cholesterol were studied in rats with lymph fistulas. After oral administration, extracts of lymph, fractionated by thin-layer chroma-tography, were found to contain the sterols, their esters and unidentified more polar compounds. In contrast to cholesterol, very little vit. D was esterified. The esters of both sterols, separated by thin-layer chromatogra-phy on the basis of the degree of unsaturation of the fatty acid moiety, were found to consist principally of saturated and monounsaturated fatty acids.

The technical assistance of Rosemarie Komen is gratefully acknowledged.