Effect of AG490 on the VSMCs Proliferation and the Expression of Bcl-2 Protein Induced by Thrombin

Objective To investigate the effect of AG490 on the VSMCs proliferation and the expression of Bcl-2 protein induced by thrombin.Methods Growth-arrested VSMCs(4-10 generation) were used in the experiments.Three groups were included:control(DMSO),thrombin(0.5 kU·L-1),thrombin(0.5 kU·L-1) plus AG490(50 mmol·L-1) respectively.Cell proliferation was quantified by MTS method at 0,1,6,12,24,48,72 h respectively.The expression of Bcl-2 protein in cells was investigated by Western blot.Results ①Compared with control group,cell proliferation was significantly enhanced by thrombin at selective time(P0.05).The proliferation curve had two peaks,one at 1 hour,and another at 24 h.Compared with thrombin group,AG490 attenuated the thrombin-induced cell proliferation at 1 h(P0.05) and at 24 h(P0.05).②The expression of Bcl-2 protein in thrombin group increased significantly at 72 h(P0.01) and at 1,12,24,48 h respectively.Compared with thrombin group,the Bcl-2 protein expression of AG490 group was decreased at 72 h(P0.01) and at 6,12,24,48 h respectively.Conclusion ①The cell proliferation induced by thrombin has two peaks at 1 hr and 24 hr.The inhibition effect of AG490 in thrombin-induced VSMCs proliferation was not only quickly and transient but also torpid and late.②AG490 can induce the apoptosis of VSMCs by down-regulating the expression of Bcl-2 protein.