Growth factors , cytokines regulate numerous critical cell functions. During the process of atherogenesis, they may act in cell recruitment and migration , cell proliferation . During the advanced stages lesions become thicker, fibrous plaques become vascularized and contain venule-like channels. These channels could play a critical role in the terminal phases of atherosclerosis, such as fissuring, cracking or ulceration, lead to hemorhage from the lumen or from these small vessels , and set the stage for the formation of a terminal thrombus . Nature of the dysfunctional changes.
Evidence suggest that oxLDL is a key component in endothelial injury .
Formation of NO can prevent platelet aggregation , on the other hand , can promote oxidation of LDL . In contrast to the LDL receptors , the scavenger receptors are not subject to down-regulation . Presence of scavenger receptors allows the cells to take up oxidatively modified LDL . Macrophages are present in all stages of atherogenesis . Macrophages internalize oxLDL through both scavenger receptors and a putative oxLDL receptor and can oxidize LDL through several pathways , including lipoxygenase enzymes .