Composition of proteoglycans from rabbit aorta in the experimentally induced atherosclerosis

Proteoglycans (PG) from normal and atherosclerotic rabbits aortas were extracted with 4 M guanidine hydrochloride and digested with collagenase in the presence of protease inhibitors. The contents of uronic acid and hexosamine from PG fractions purified by isopycnic CsCl gradient ultracentrifugation under associative and dissociative conditions were significantly higher in the atherosclerotic aortas (up to 40%) than in the control tissue. The uronic acid/protein ratio increased from 0.7 to 1.3 in the monomers PG fraction of atherosclerotic aortas. Chromatographic separation and electrophoretic analysis of PG monomers indicated the presence of three different subfractions PGI, PGII and PGIII in both groups of animals. The uronic acid/protein ratio in PGI from experimental aorta was increased whereas this ratio in PGIII was decreased compared to contrast tissue. The observed increase of sugar component in the core proteins suggests their over glycosylation.