Temporal pattern of Ang-2 secretion. (A) Stimulation of Ang-2 release by PMA leads to detection of Ang-2 in the supernatant of stimulated cells within 5 minutes and reaches maximum concentration after 20 minutes. (B) PMA-induced secretion of Ang-2 parallels the temporal pattern of VWF secretion. The decline in the intensity of Ang-2 and VWF staining runs in parallel. Both Ang-2 and VWF become essentially undetectable after 30 minutes of PMA stimulation. Original magnification, × 40.