Abstract: Objective To observe the effect of tea polyphenols(TP)on cell adhesion molecules expression of humanum bilicalvein endothelial cells(HU VEC)induced by homocysteine.Methods HU VEC in logar ithm growth per iod were divided into control group and 3 experimental groups,which were TP,Hcy,and Hcy+T P respect ively.The final concentrations of TP and Hcy in medium were 25 mg/L and 5 mmol/L respectively.Control group were treated with equal volume of PBS.After 24 hours administered with TP and/or Hcy,cell viability was determined by methyl thiazolyl tetrazolium(MTT)assay,the expression of inter cellular adhension molecule-I(ICAM-1)and E-selectin were analyzed by immunocy to chemistry.Results MTTresults showed that TP had no effects on HU VEC at 25 mg/L.Hcy inhibited the cell proliferation rate by 36.0%(P<0.05),and T P decr eased the effects of Hcy on HUV EC(7.9%,P<3.05).The results of immunocytoche mistry also showed that the expr ession of ICAM-1 and E-selectin in group of Hcy increased by 29 9% and 37.7%(P<0.05)respectively compared with the control group,while TP could inhibit the effects of Hcy,decreased the expression of ICAM-1 and E-selectin by 17.9% and 24.6%(P<0.05).Conclusion TP could reverse the changes of the expression of ICA M-1 and E-selectin induced by Hcy on HUV EC.