Abstract: Aim：To explore the relationship between the levels of tumor necrosis factor related apoptosis inducing ligand (TRAIL) and death recrptor 5 (DR5) and atherosclerosis(AS). Methods：The 83 patients were divided into two groups: 61 in the coronary artery disease (AS) group and 22 in the nonAS group. Plasma TRAIL and DR5 levels from these people were assayed by ELISA. The 20 sections from coronary arteries were also divided into two groups: 10 in each group. The levels of TRAIL and DR5 protein expression were detected by immunohistochemisty statining. Results：Plasma TRAIL and DR5 levels were significantly increased in the ACS group （1293.30pg/ml±138.17pg/ml vs.333.11 pg/ml±246.15 pg/ml, P=0.000；43.08 pg/ml±16.19 pg/ml vs.34.70pg/ml±13.68 pg/ml, P=0.033）. Plasma TRAIL and DR5 levels in patients with 3-vessel involved CAD were significantly higher than those in patients with no- and 1-vessel. So was patients with 2-vessel. Both TRAIL and DR5 were found expressed in endochylema of vascular smooth muscle cell. TRAIL protein expression was also detected in macrophage. There was a markedly higher expression in AS group than nonAS group(65.48±1.27 vs. 18.66±1.02, P<0.01 and 60.23±1.09 vs.30.15±1.16，P<0.05, respectively） Conclusions：TRAIL were expressed in endochylema of macrophage. Both TRAIL and DR5 may contribute to the development of AS. The higher levels of plasma TRAIL and DR5, the greater the degress of coronary arteries lesions would be.

Key words: TNF related apoptosis inducing ligand, receptor, atherosclerosis, apoptosis, immunohistochemistry