Role of glycosaminoglycans in altering vascular wall permeability for atherogenic lipoproteins

: The relationship between the pattern of distribution of lipoproteins and morphological features of atherosclerotic lesions was demonstrated by histoautoradiographic and histochemical methods in experiments using perfusion in vitro of aortas from atherosclerotic rabbits with atherogenic lipoproteins (LP) labeled in various positions. Accumulation of glycosaminoglycanes (GAG) in the time course of the atherosclerotic process was shown to be the factor contributing to the retention of LP in the vessel wall. At the same time, no GAG accumulation was found in sites of the greatest permeability. Irrespective of the stage of the process, formation of foci of increased permeability was, as a rule, associated with accumulation of poorly differentiated cells. The evidence of primary increase of permeability of the endothelial barrier in the form of activation of the proliferative processes and GAG accumulation was obtained.