The chemical compositions of the thoracic aorta in diabetics and nondiabetics.

Chemical analysis of the composition of the thoracic aorta was performed in 19 age- and sex-matched pairs of diabetic and nondiabetic autopsy subjects. Contents of total lipid, cholesterol, triglyceride, phospholipid, free fatty acid and collagen in the aortic wall were greater in cases with advanced atherosclerosis than in those with less advanced atherosclerosis. According to severity of atherosclerosis, the ratio of cholesterol to total lipid in the aortic wall increased, while the ratios of triglyceride, phospholipid and free fatty acid to total lipid decreased. The cholesterol concentration in the aorta increased with dry weight of the aorta per area. The rate of increase was 2.6 times higher in diabetics than in nondiabetics. These results suggest that content of cholesterol in the aortic wall increases markedly according to the advance of atherosclerosis, especially in the diabetics.