Redistribution of Lipid in Rat Liver Homogenates

Abstract

WHEN a homogenate of rat liver is subjected to high centrifugal forces a creamy layer of lipid appears on the surface of the clear supernatant^1,2. In choline deficiency this ‘floating’ or ‘free’ lipid increases in parallel with the increase of liver triglycerides³. It may also be measured by extraction of the homogenate with non-polar solvents⁴. In the course of our work on the effects of short-term choline deficiency in the rat, we observed a decrease of this lipid fraction during storage of the homogenate at 1° C. We examined this phenomenon at body temperature under more controlled experimental conditions and, furthermore, compared the fall of the floating lipid with other lipid changes in the clear supernatant and in the sediment that occurred during the same period of incubation.