Serum lipids after intravenous and intragastric fat emulsion in man.

C ONSIDERABLE experience has been gained with the clinical use of fat emulsions for parenteral alimentation. Recently, a safe utilizable emusion for short term use has become available, and as more experience has gained, it has become possible to study the physiologic changes taking place in the removal of fat from the circulation. Initial observations by Mueller’2 have shown that there was great variation in the time required to clear fat from the blood stream, not only in different patients, but also in the same patient under varying circumstances. The mechanisms which regulate the disappearance of particulate lipid from blood are poorly understood, as are many of the other steps in lipid transport. It appeared to us, therefore, that fat emulsion might be a tool with which certam aspects of fat transport could be studied. The experiments described herein were designed to explore the role of the various serum lipid components in the removal of infused particulate fat. An umipublished preliminary study was performed on nine normal volunteer subjects and nine hospitalized patients. The results served as a basis for the present studies in which the method of Van Eck, Peters and Man3 for the separation of serum lipids into the “soluble and insoluble’ ‘ fractions by high speed centrifugation was utilized. The present study lends further support to the theory that ‘ ‘soluble’ ‘ lipoprotein plays a role in the mechanisms involved in the transport of neutral fat. METHODS AND PROCEDURE