Regulation of Angiogenic Functions by Angiopoietins through Calcium-Dependent Signaling Pathways

Figure 5

Calcium-dependent AKT and MAPK activation upon Ang-1/Ang-2 stimulation. Ang-1 and Ang-2 induce Ca²⁺-dependent AKT, ERK1/2, and p38 phosphorylation. Confluent HUVECs were pretreated or not with 20 μM BAPTA-AM for 1 h and stimulated with 100 ng/mL Ang-1 or 200 ng/mL Ang-2 for 30 min. Blots of total cell lysate were probed for the phosphorylation of downstream targets AKT, ERK1/2, and p38. To ensure equal loading membranes were reprobed for the total amount of the indicated proteins and for β-actin. Representative blots are shown from three to five independent experiments (a). Cells pretreated or not with 75 μM 2-APB or 30 μM 8Br-cADPR and stimulated with either Ang-1 or Ang-2. Blots of total cell lysate were probed for the phosphorylation of downstream target AKT. To ensure equal loading membranes were reprobed for the total amount of the indicated protein and for β-actin. Representative blots are shown from three independent experiments (b1, b2, c1, and c2).

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