Electron microscope studies of the absorption of lipids: I. Oxidized cod liver oil

Abstract

The pathway of absorption of ethyl esters of a fraction (fraction 7) of a molecular distillate of oxidized cod liver oil has been traced by electron microscopy. The observations are consonant with the concept that the fatty acids, glycerol and monoglycerides are absorbed across the cell membrane and are resynthesized within the endoplasmic reticulum into triglycerides. No evidence of pinocytosis of lipid droplets was observed at the cell surfaces. The epithelial cell appears to be capable of segregating relatively unsaturated from relatively saturated fatty acids and to elaborate the two in the form of electron dense or electron lucent chylomicrons. Liver cells share this ability to segregate unsaturated from saturated lipids. These experiments demonstrate the importance of ingested lipid, specifically oxidized lipid, in the development of disease. It is suggested that a noxious agent is carried across the cell and into the blood stream by the absorptive process, with ultimate severe damage to cell membranes and to blood platelets, ending in pregnant animals in a lethal episode of disseminated intravascular coagulation.