We examined the effect of estradiol-17 beta on the expression of vascular cell adhesion molecule-1 (VCAM-1), an adhesion molecule, in human umbilical vascular endothelial cells. After preincubation with estradiol-17 beta for 24 hours, cells were treated for 4 h with 0.5 micrograms/ml recombinant human interleukin-1 beta. The RNase protection assay was performed using an [alpha-32P]-labeled 121 base pair VCAM-1 cRNA probe. Preincubation with estradiol-17 beta (250 or 500 pg/ml) suppressed the induction of VCAM-1 mRNA expression by interleukin-1 beta. VCAM-1 staining with a monoclonal antibody decreased when cells were incubated with estradiol-17 beta at 250 and 500 pg/ml, while staining was detectable when cells were treated with interleukin-1 beta at 0.5 micrograms/ml. In conclusion, estradiol-17 beta regulates the induction of VCAM-1 gene expression by interleukin-1 beta in human umbilical vein endothelial cells.