The effect of varying concentrations of dilazep on TF activity expression on HUVECs stimulated with TNF, thrombin, or PMA. HUVECs were treated for 5 hours with each stimulant. (A) 1,000 U /mL TNF, (B) 25 nmol/L thrombin, and (C) 5 nmol/L PMA in the presence of varying concentrations of dilazep (0 to 100 μg/mL). TF activity on HUVEC surface was determined as factor Xa generation using the S2222 (see the Materials and Methods). The data are expressed as the percentage of the control (each stimulant induced TF activity in the absence of dilazep). The values represent the mean ± SD of four independent experiments.