Disappointment with triethers as markers for measuring triglyceride absorption in man.

Glycerol triethers were tried as non-absorbable, oil-phase markers for indirectly measuring triglyceride absorption in the human proximal jejunum. Tritium labelled 1-hexadecyl-2, 3-didodecyl glycerol, or 1,2,3-trioleyl glycerol, or 1,2,3-tridecyl glycerol was dissolved in linseed oil and egg yolk lipids; an aqueous emulsion of the lipid mixture was infused into the stomach. Unexpectedly, postprandial jejunal contents contained proportionately less triether than triglyceride compared with the test meals. These triethers were found to separate from an aqueous phase at a faster rate than the triglyceride. This dissociation occurred in the stomach and thwarted quantification of triglyceride absorption by this test system.