Effect of infusions of phosphatides upon the atherosclerotic aorta in situ and as an ocular aortic implant*

Abstract

Rabbits fed cholesterol- and oil-supplemented diet were carefully paired for equality of plasma cholesterol concentration during the feeding period and a subsequent 30 days of normal diet. The normal diet was continued and one of each pair of rabbits was then subjected to intravenous infusion of mixed phosphatides of animal or soybean origin twice weekly for an average of 11 infusions. At the end of this time the aortas of the infused rabbits showed markedly less atherosclerosis than their paired controls, both grossly and when assessed on the basis of cholesterol content. When implants of atherosclerotic aorta were made into the anterior chamber of the eyes of normal host rabbits, infusions of phosphatide did not accelerate the decline in cholesterol content of the implants or affect the normal cholesterol content of the host rabbit's own aorta. When normal rabbit aorta was implanted into normal host rabbits thereafter fed a diet enriched in cholesterol and oil, infusion of phosphatide had no effect on atherosclerosis of the host's own aorta. However, a marked increase was observed in sudanophilia and cholesterol content of the aortic implants in those rabbits receiving infusions. Apparently the lipid dynamics of ocular aortic implants differs from that of the aorta in situ. Infusions of phosphatide can alleviate atherosclerosis when a cholesterol-free dietary is followed but may worsen atherosclerosis when a cholesterol-free diet is not followed.