Effect of hyperchylomicronemia and hyperprebetalipoproteinemia on the vascular wall in rats of various ages

Abstract

The effect of hyperchylomicronemia and hyperprebetalipoproteinemia on the vascular wall was studied in rats aged 6–10 and 26–30 months. The animals were given an intravenous injection of blood serum from rats which themselves had previously been injected intraperitoneally with Triton WR1339. Inclusions of chylomicrons and liporoteins of very low density were found electron-microscopically in the endothelium of the old rats only. Swelling of the Golgi complex and mitochondria and dilatation of the cisternae of the endoplasmic reticulum in the endothelial cells of the young rats indicated activation of intracellular metabolism. The study of biosynthesis of certain classes of lipids in the aorta under these conditions showed inhibition of biosynthesis of free cholesterol, the intensity of which was the same in rats of different ages. Increased phospholipid biosynthesis was observed only in the young animals.