Endothelial network formation is regulated by endothelial PGF
-FP receptor interaction. (A) Expression of FP receptor in HUVECs incubated with V CM or P CM for 1,2,3,4,6,16 and 24 hrs as determined by quantitative RT-PCR analysis. (B) FP receptor mRNA in HUVECs incubated with V CM or P CM for 3 hrs in the absence/presence of FGFR1 tyrosine kinase inhibitor SU4984 or ERK1/2 inhibitor PD98059 as determined by quantitative RT-PCR analysis. HUVECs were incubated with vehicle or exogenous PGF2α (1 μM) and endothelial cell network formation (C) and proliferation (D) were assessed. HUVECs were infected with scrambled adenovirus (scr) or short hairpin adenovirus targeted against the FP receptor (sh478) and treated with V CM or P CM. Endothelial network formation (E) and proliferation (F) was determined as described in the methods. (G) HUVECs were incubated with V CM or P CM in the absence/presence of NS398 or indomethacin and network formation was assessed. Data are expressed as fold or percentage increase over control V CM (V CM = 1 or 100%, not shown) and represented as mean ± SEM. (* represents statistical significance P < 0.05).