Intestinal lymph chylomicron cholesteryl ester during duodenal triolein infusion at increasing rate.

Chylomicron lipid composition in mesenteric lymph fistula rats was followed during duodenal triolein infusion at three rates. Esterified cholesterol decreased progressively in all groups as triglyceride transport continued, and the rate of decrease was reciprocally related to the triolein infusion rate. Suppression of cholesterol ester synthesis may spare unesterified cholesterol for chylomicron membrane formation. Ratios of triglyceride to phospholipid and to unesterified cholesterol increased with the duration of triglyceride secretion, while the chylomicron surface lipid composition remained constant over time. The rate of increase in the core:surface lipid ratios was the same irrespective of the triolein transport rate.