[Expression of ABCA1 in vascular endothelial cells and its significance in the pathogenesis of atherosclerosis].

To investigate the changes in the expressions of ATP-binding cassette transporter A1 (ABCA1), intercellular cell adhesion molecule type 1 (ICAM-1) and monocyte chemoattractant protein-1 (MCP-1) at mRNA and protein levels after the treatment of the vascular endothelial ECV304 cells with oxidized low-density lipoprotein (Ox-LDL) and 8-Br-cAMP, thereby to explore possible mechanisms by which ABCA1 affects the formation of atherosclerosis (AS).Resuscitated and cultured ECV304 cells were incubated in serum-free medium for 12 h to induce the quiescence phase of growth, which were subsequently treated with Ox-LDL (30 ng/ml) and 8-Br-cAMP (0.5 mmol/L) respectively for 3, 6, 12, and 24 h. After the cells were harvested at the specified time points, the mRNA and protein levels of ABCA1, ICAM-1 and MCP-1 were detected by RT-PCR and Western blotting, respectively.The mRNA and protein expression levels of ABCA1, ICAM-1 and MCP-1 all increased after treatments with Ox-LDL and 8-Br-cAMP. The highest expression of ICAM-1 occurred in cells with a 12-hour treatment, and those of ABCA1 and MCP-1 occurred following 6-hour incubation with Ox-LDL. The expression peaks of ABCA1, ICAM-1 and MCP-1 all took place after 6-hour incubation with 8-Br-cAMP.The mRNA and protein expressions of ICAM-1 and MCP-1 in vascular endothelial ECV304 cells increase in response to Ox-LDL treatment, in the event of which ABCA1 is also up-regulated to offer protective effects against AS. cAMP not only enhances the expression of ABCA1 but also those of ICAM-1 and MCP-1.