FVIIa prevents thrombin-induced cytoskeletal rearrangement. HUVEC monolayers were treated with a control vehicle (A-B) or FVIIa (10nM; C) for 2 hours, and then with thrombin (5nM) for 10 minutes (B-C). The cells were fixed, permeabilized, and stained with rhodamine-conjugated phalloidin to detect F-actin. Cells were imaged using a confocal system (LSM 510 META; Zeiss) equipped with an Axio Observer Z1 microscope (Zeiss).