Lipid composition of rabbit aortic wall following removal of endothelium by balloon catheter.

To determine the lipid content of the neointima formed following balloon catheter deendothelialization, we measured the chemical composition of intimal medial samples of the aortic wall of rabbits at 6, 12, and 24 months after the operation. The areas of endothelial regrowth and the denuded areas were outlined by intravenous injection of Evan's blue dye. Lipids were extracted by chloroform/methanol (2:1, vol/vol) separated by thin-layer chromatography, eluted, and estimated by gas-liquid chromatography. No tendency to regression was observed. By contrast we observed a progressive increase over time in the concentration of most lipid classes in the areas of endothelial regrowth. There is evidence indicating that the increase in the lipid concentration parallels the increase in the glycosaminoglycan content in the areas of endothelial regrowth. It is possible that endothelial injury causes some irreversible changes in the composition of the neointima in areas of endothelial regeneration.