Effect of dietary restriction on the plasma apolipoprotein pattern in cholesterol-fed rabbits.

Dietary restriction (half of the control ration) was performed in rabbits given either standard or cholesterol-rich diets. The plasma apolipoproteins were studied on the total, d less than 1.21, lipoprotein fraction using polyacrylamide gel electrophoresis. A marked rise in the amount of both apo-B and apo-E appeared in cholesterol-fed rabbits and was enhanced by dietary restriction. These results reflect the aggravation of hypercholesterolemia when cholesterol feeding is carried out in underfed rabbits. In all groups only one molecular species of apo-B, identified as apo-B-100, was present after overnight fasting. Thus, lipoproteins which accumulate in the plasma following cholesterol feeding, associated with dietary restriction or not, probably are remnants of hepatogenous triglyceride-rich lipoproteins.