Azaspirane inhibits generation of capillary vessels on HUVECs. HUVECs were cultured in 96-well plates with ECMatrix with or without azaspirane (Aza; 1.25 and 2.5 μM) (magnification, × 40) (A). Cytotoxicity of azaspirane (0-5μM) against HUVECs was determined at 24 hours by MTT assay (B), and VEGF levels in culture supernatants were measured by ELISA (C), and data represent mean (± SD) of quadruplicate cultures. ^*P < .01.