Effect of staurosporine and wortmannin on endothelial CD31-induced increase in the adhesive function of vβ3 integrin to RGD peptide. ⁵¹Cr-labeled HUVECs were preincubated with staurosporine (Staur; 10⁻⁸ mol/L), wortmannin (Wort; 10⁻⁷ mol/L), or the combination of them for 10 minutes at 37°C and were then preincubated with anti-CD31 MoAb (CD31) or control mouse IgG (Cont) (10 μg/mL each) for 10 minutes at 37°C. After washing the cells, the binding assay of ⁵¹Cr-labeled HUVECs to RGD peptide was performed for 10 minutes at 37°C. Data are the means ± SD for 6 to 8 experiments. *Significantly different from the mean value of the control response of anti-CD31 MoAb-pretreated HUVECs (*P < .001). **Significantly different from the mean value of the responses of anti-CD31 MoAb-pretreated HUVECs in the presence of staurosporine or wortmannin alone, respectively (**P < .05).