Lipid Oxidation in the Development of Fatty Streak

Trapping of LDL ill the Artery Wall The earliest event in the development oj the j'at!}' streak is the transport of LDL into the ariel}' wall. This is a concentration dependent process that does not require receptor mediated endocytosis':', The late Tom Carew and his colleague Dawn Schwenke demonstrated':' that for any given concentration of lipoprotein in the plasama, lipoprotein retention in the artery wall was more important than, the rate of transport into the arterywall. Knlth5 and the Simionescus" were among the first to report changes in the lipoproteins that were retained in, the artery wall. With state-of-the-art ultrastructural techniques Frank et of.7 extended these findings and demonstrated in exquisite detail the three dimensional cagework offibers and fibrils secreted hy the cells ojthe artery wall into the subendothelial space. Nivelstein-post' demonstrated that when LDL was in, jectedinto a normal rabbit, it rapidly' crossed the intact endothelium and became trapped in this three dimensiona I cage work subsequently, Nivelstein-post' demonstarted that LDL associates with the collagen fibers in, the vicinity of the cross connecting fibrils. The intimate association of L.DL with the extracellular matrix of' the subendothelial space described by Camejo and colleagues" explain why higher concentrations of apolipoprotein B are present in the artery wall than in the plasma