MVs induced Akt activation and expression of Bcl-xL and eNOS. Cell lysates (30 μg of protein) were immunoblotted with anti–P-Akt, -Akt, – Bcl-xL or -βactin Abs. (A) Densitometric analysis of P-Akt/Akt ratio. Data of P-Akt/Akt ratio are expressed as mean (± 1 SD) from 3 different experiments. (B) Representative immunoblots of P-Akt, Akt, and Bcl-xL expression. Control HMECs were serum starved for 24 hours. HMECs serum-starved were stimulated with 10 μg/mL MVs or RNase-treated MVs for 24 hours. (C) Incubation of HMECs with MVs induced expression of e-NOS; the eNOS activation was indicated by its phosphorylation at ser1177 (P-eNOS). (D) Organization of HMECs into capillary-like structures on Matrigel was inhibited by PI3K inhibitors wortmannin (0.1 μM) and LY294002 (10 μM) and by the NOS inhibitors L-NAME (10 μM) and L-NMMA (10 μM). D-NAME and D-NMMA were ineffective. Data are expressed as mean (± 1 SD) from 3 different experiments. Analysis of variance with Newmann-Keuls multicomparison test was performed; *P < .05 MVs, MV + D-NAME or MVs + D-NMMA versus vehicle; §P < .05 MVs + PI3K or NOS inhibitors versus MVs.