Modulation of Rac1 and RhoA activity induced by Ang-1. (A) Starved, subconfluent ECs stimulated with Ang-1 (20 ng/mL) or vehicle underwent pull-down assays. The leftmost lanes indicate Rho GTPase activity in the presence of FCS (20%). (B) The results of densitometric analysis of Rac1-GTP (▦) and RhoA-GTP (▪) were normalized to total Rac1 and RhoA in whole cell lysates and expressed relative to the basal value of cells maintained in 20% FCS. (Means ± SDs of 5 independent experiments; ^*P < .05 versus starved unstimulated cells by Student t test).