Abstract:Aim To observe the regulation of stromal derived factor 1(SDF-1) on monocytes-endothelial cells induced by low density lipoprotein (LDL). Methods LDL was separated by density gradient centrifugation. Reverse transcript-polymerase chain reaction (RT-PCR) and Western blot were separately used to detect the expression of mRNA and protein of SDF-1 in endothelial cells. Cell counting was used to observe the effect of the adhesion of monocytes/endothelial cells treated with LDL or SDF-1 antibody. Results Compared with the control group, the level of expression in LDL treated groups increased evidently as the LDL concentration increased. The adhered amount of monocytes to endothelial cells were 60±20, 97±26, 170±32, respectively responding to the LDL concentration 50 mg/L, 100 mg/L, 150 mg/L. And the amount was 20±5 in the control (p<0.01). While endothelial cells were incubated with SDF-1 antibody with 0.1 mg/L, 0.5 mg/L, 1 mg/L respectively before LDL incubation, the adhesion of monocytes was 113±23, 53±21, 41±10 respectively. They were significantly lower than that of control group (186±31) (p<0.05). Conclusion LDL increased the adhesion between monocytes and endothelial cells, which is closely correlative to the increasing expression of SDF-1 in endothelial cells.