Metabolism of chylomicrons of differing triglyceride composition

Abstract

Lymph chylomicrons of widely different fatty acid composition were obtained from donor animals fed either cream and palmitic acid-9,10-H3 or corn oil and linoleic acid-1-C14. The rates of removal of these two types of chylomicrons from the circulation of recipient dogs and rats were determined from the relative rates of removal of the two isotopes and in some cases by changes in the fatty acid composition of the plasma chylomicrons.In intact dogs and rats, the removal of cream chylomicrons was the more rapid. In dogs the H3/C14 ratio in hepatic venous blood was lower than that in femoral venous blood. In livers of rats, there was a greater percentage uptake of radioactivity associated with cream chylomicrons than of that associated with corn oil chylomicrons, but similar amounts were recovered from adipose tissue.When livers of rats were perfused with the two types of chylomicrons, the rate of removal of cream chylomicrons from the perfusate was greater. On the other hand, cream and corn oil chylomicrons were removed in similar amounts when adipose tissue of rats was perfused.