In vitro activity: ZM323881 inhibits VEGF-A, EGF and bFEF induced HUVEC cell proliferation with IC50 of 8 nM, 1.9 μM and 1.6 μM, respectively. ZM323881 (10 nM) abolishes VEGF-A-mediated increases in vascular permeability in perfused mesenteric microvessels in male leopard. ZM323881 (10 nM) blocks the increase in intensity of the VEGF-R2 band in the lung of male leopard frogs. ZM323881 (1 μM) blocks activation of extracellular regulated-kinase, p38, Akt, and endothelial nitric oxide synthetase (eNOS) by VEGF, but did not inhibit p38 activation by the VEGFR-1-specific ligand, placental growth factor (PIGF) in human aortic endothelial cells (HAECs). ZM323881 (1 μM) also perturbes VEGF-induced membrane extension, cell migration, and tube formation by HAECs. ZM323881 (1 μM) reverses VEGF-stimulated phosphorylation of CrkII and its Src homology 2 (SH2)-binding protein p130Cas, which are known to play a pivotal role in regulating endothelial cell migration. ZM323881 (10 nM) completely blocks VEGF-induced VEGF promoter activity in SCC-9 cells. ZM323881 (10 nM) blocks VEGF stimulated Hif-1α protein accumulation in SCC-9 cells. ZM323881 (10 nM) blocks VEGF-induced Rac1 activation at 30 min in HUVECs. ZM323881 (10 nM) prevents Vav2 tyrosine phosphorylation in response to VEGF in HUVECs. ZM323881 (< 1 μM) inhibits VEGF stimulated neural stem cell proliferation in a dose-dependent manner. ZM323881 (< 1 μM) inhibits neural stem cell proliferation in a dose-dependent manner even when no exogenous VEGF is added.

Kinase Assay: Compounds (ZM323881) are incubated (20 minutes, room temperature) with enzyme in an N-2-hydroxyethylpiperazine-N'-2-ethanesulphonate (HEPES) (pH 7.5) buffered solution containing 10 mM MnCl2 and 2 μM ATP, in96-well plates coated with a poly(Glu, Ala, Tyr) 6:3:1 random copolymer substrate. Phosphorylated tyrosine is then detected bysequential incubation with mouse IgG anti-phosphotyrosine antibody a horseradish peroxidase(HRP)-linked sheep anti-mouse Ig antibody and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid). IC50 data are interpolated by nonlin-ear regression

Cell Assay: HUVEC cells isolated from umbilical cords are plated (at passage 2–8) in 96-wellplates (1000 cells/well) and dosed with ZM323881±VEGF-A (3 ng/mL), EGF (3 ng/mL), or basicfibroblast growth factor (bFGF, 0.3 ng/mL). The cultures are then incubated for 4 days. On day 4, the cultures are pulsed with 1 μCi/well of 3H-thymidine and reincubated for 4 hours. The cells are then harvested and assayed for the incorporation of tritium by using a beta-counter. IC50 data are interpolated

Microcirculation. 2002 Dec;9(6):513-22; Biochem Biophys Res Commun. 2006 Apr 14;342(3):851-8.