Abstract:

Objective To investigate the effects of glucose and insulin on the production of solubility endothelial cell protein C receptor(sEPCR) in human umbilical vein endothelial cells ( HUVEC) and to clarify the  mechanisms of the damage of vein endothelial cells and the diabetic thrombosis. Methods HUVEC  cultivated in vitro were divided into glucose (Glu) groups (5.5,20.0 and 40.0 mmol/L），insulin groups（0.1,1.0 and 10.0 nmol/L），insulin groups（0.1，1.0 and 10.0 nmol/L） in high glucose environment（40 mmol/L）and control group (without glucose and insulin). The cell supernatant was collected at different time (0，6，24，48 and 72 h) and the levels of sEPCR were detected by ELISA assay. Results The levels of sEPCR of HUVEC in Glu groups were higher than that in control group （P<0.01）,and it was gradually increased with the prolongation of time. But the level of sEPCR at high concentration of Glu （40 mmol/L） was decreased after the cells  were cultured for 48 h（P<0.01）. The level of sEPCR of HUVEC in insulin group was higher than that in  control group （P<0.01）,  and it was gradually increased with the prolongation of time. But the level of sEPCR at high concentration of Glu（40 mmol/L）  was decreased after the cells were cultured for 72 h （P<0.01）.The levels of sEPCR at high concentration of Glu with different concentrations of insulin were lower than the levels of those cultured with Glu（P<0.01）.Conclusion Insulin can inhibit the damage effect of high concentration Glu on HUVEC,but long-time use of high concentration insulin can aggravate the damage of HUVEC and induce thrombosis.   

Key words:  human umbilical vein endothelial cells;endothelial cell protein C receptor;glucose;insulin