Lipoprotein changes induced by intravenously administered lipid emulsion leading to arteriosclerotic lesions in the rat.

Intravenous administration of Lipofundin-S oil, in the rat induces arteriosclerotic lesions within several days. Changes in lipids and lipoproteins were studied by lipid electrophoresis, ultracentrifugation and gel filtration. One hour after injection of Lipofundin, a dramatic increase occurred in triglycerides and phospholipids, reflecting the composition of the lipid emulsion. During a period of 6-7 h the lipid concentrations normalized by hydrolysis. Repeated injections (every 12 h) of Lipofundin-S led to persisting changes in the lipoprotein concentrations within 2-4 days. Very-low-density and high-density lipoprotein (alpha-lipoprotein) levels decreased, whereas low-density lipoprotein (beta-lipoprotein) levels increased. The beta-/alpha-lipoprotein ratio, as determined from the peak areas of the lipoprotein electrophoresis pattern, increased significantly. The alterations of this 'atherogenic index' may cause the atherosclerotic lesions observed in the aorta of animals which are normally resistant to atherosclerosis.