Figure 3: Effect of tryptase on the VEGF, Flt-1, and Flk-1 mRNA levels in HDMECs. Different concentrations of tryptase (0, 1, and 10 nmol/L) were added into HDMECs for 6 h. The mRNA levels of VEGF (a), Flt-1 (b), and Flk-1 (c) were determined by Real-time RT-PCR and normalized to GAPDH. The heparin control was also analyzed. 𝑃 < 0 . 0 5 compared to the group of heparin control.