Abstract: Objective To validate the apoptosis of HUVECs induced by hemodialysis patients seum and explore the mechanism.Methods HUVECs are exposed to culture medium containing serum obtained from patients undergoing haemodialysis(trial group) and healthy volunteers(control group).The effect of uraemic serum on the apoptosis of endothelial cells in vascular networks are observed under light-microscope;Cell proliferation are measured by MTT;Apoptotic cells in vascular networks are evaluated by TUNEL;To investigate the expression of caspase-3 and production of ROS, cell lysates are evaluated by western blotting and spectrophotometry.Results After HUVECs are exposed to pooled serum medium for 40 h, there are apoptotic endothelial cells in vascular networks (P＜0.05) and the endothelial cells produce more ROS in trial group(P＜0.05).At 40h, the expression level of caspase-3 in endothelial cells in trial group is（0.83±0.03）,significantly higher than in control group（0.57±0.02）（P＜0.05）.Conclusion Hemodialysis patients serum can induce apoptosis of HUVECs in vascular networks. Higher expression of caspase-3 and more production of ROS in endothelial cells may be involved in the mechanism.

Key words: hemodialysis, endothelial cells, apoptosis, angiogenesis