EXPRESSION OF MONOCYTE CHEMOATTRACTANT PROTEIN-1 IN VASCULAR TISSUE

We investigated monocyte chemoattractant protein-1 (MCP-1) mRNA expres sion in rat vascular smooth muscle cells (VSMC) and in human atheroscl erotic arteries to test the involvement of MCP-1 in the pathogenesis o f atherosclerosis. In Northern blot analysis, MCP-1 mRNA expression wa s not observed in unstimulated cultured rat vascular smooth muscle cel ls (VSMC), but its expression was clearly observed by exposure to tumo ur necrosis factor-alpha (100 U/ml) for 2-6 h. Mitogen-activated prote in kinase activity in VSMC incubated in serum-free culture medium was increased by exposure to 0.5% fetal bovine serum, while the effect was significantly suppressed in the presence of MCP-1 (100 ng/ml), We the n evaluated MCP-1 mRNA expression in atherosclerotic arteries obtained from 12 patients undergoing bypass revascularization through reverse transcription-polymerase chain reaction analysis and observed MCP-1 mR NA expression in all atherosclerotic arteries studied. These results s upport the premise that MCP-1 is secreted by VSMC in atherosclerotic p laques as well as by endothelial cells and macrophages and contributes to the pathogenesis of atherosclerosis. (C) 1995 Academic Press Limit ed.