Atherosclerosis is a chronic inflammatory disease leading to the formation of vascular plaques within the major arteries. Vascular plaques consist of a collection of inflammatory cells, extracellular matrix and fibrous material. Advanced plaques are characterised by the formation of necrotic zones often containing free lipid deposits high in cholesterol esters. Though considerable work has been published on the contents of these atherosclerotic plaques very little is known about how the

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... ion varies along the length of the plaque. Nor is it known whether the pterin, 7,8-dihydroneopterin, is released by activated macrophages at levels where it can alter the plaque development through it's antioxidant activity. Atherosclerotic plaques were removed from patients carotid and femoral arteries during endarectomy surgery and sliced into 3-5 cm sections along the length of the plaque. For each segment the concentrations of neopterin, 7,8-dihydroneopterin, α-tocopherol, TBARS, DOPA, dityrosine, the protein carbonyls α-Aminoadipic semialdehyde (AAS) and γ-glutamic semialdehyde (GGS), 7-ketocholesterol, and cholesterol was measured. Plasma samples were taken from around the sites of coronary plaques during angioplasty procedures and the concentrations of neopterin and 7,8-dihydroneopterin was measured. The oxidant, antioxidant and inflammatory markers analysed in the atherosclerotic plaques showed many strong positive correlations between pairs of markers. The strongest was between α-tocopherol and cholesterol with significant correlations in the majority of plaques analysed. Combined plaque data analysed by dividing the segments up into three zones, pre-bifurcation, bifurcation and post-bifurcation showed that the formation of both protein and lipid oxidation markers were significantly high in the prebifurcation zones while alpha tocopherol was highest in the post-bifurcation zone but failed to reach significants. The pre-bifurcation zone is thought to be associated with a low shear stress level in the plaque and the [...]