Very low density lipoproteins in normal and cholesterol-fed rabbits: lipid and protein composition and metabolism. Part 2. Metabolism of very low density lipoproteins in rabbits.

The metabolic fate of very low density lipoproteins (VLDL) in normal and hypercholesteremic (h.c.) rabbits has been investigated. VLDL were labelled with 125I in the protein moieties and injected into normal and h.c. animals. The turnover of h.c. VLDL is markedly delayed as compared to that of normal VLDL, and conversion into lipoprotein classes of higher density is considerably decreased. This is observed when h.c. VLDL are injected either into h.c., or into normal rabbits. Arterial uptake of radioactivity is much higher with h.c. VLDL than with the normal lipoproteins, and it is highest when h.c. VLDL are injected into normal recipients. These data, together with those reported in the previous study, support the hypothesis that h.c. VLDL have an inherent atherogenicity. Injection of h.c. VLDL into normal animals also offers an experimental model for testing drugs or diets against atherosclerosis, using untreated animals.