The Role of Thrombin on VSMCs Proliferation

Objective To study the effect of thrombin on cultured Vascular Smooth Muscle Cells(VSMCs)proliferation.Methods Growth-arrested VSMCs were used in the experiment.Quiescent cells were exposed to control or thrombin(0.1,0.5,1,3,10 U/ml)and proliferation was quantified at 24 h.The cells were also exposed to control or thrombin(0.5 U/ml and 1.0U/ml)respectively and the cell proliferation was quantified at 0,1,6,12,24,48,72 h respectively.Results ①Thrombin-at various concentrations(0.1～10 U/ml) significantly induced VSMCs proliferation at 24 h(P0.05),but the effects of various concentrations of thrombin(0.1～10 U/ml)were similar to each other (P0.05).②Compared with control group,cell proliferation was significantly induced by thrombin(0.5 U/ml and 1U/ml)at selective time(1,6,12,24,48,72 h)(P0.05),and two proliferation curves were similar(P0.05).The proliferation curve had two peaks,one at 1 hour,and the other at 24 h.Conclusion ①thrombin stimulated proliferation of VSMCs in a dose-independent with concentration from 0.1 U/ml to 10U/ml.②The cell proliferation induced by thrombin has two peaks at 1 hr and 24 hr.