Figure 2. Cytotoxicity of norisoboldine (NOR) against HUVECs.

(A) MTT assay. HUVECs seeded in 96-well plate were incubated with NOR (1, 3, 10, 30, 60, 100 µM) for 24 h. Then MTT assay was used to evaluate the viability. (B) LDH assay. HUVECs seeded in 96-well plate were incubated with NOR (1, 3, 10, 30, 60, 100 µM) for 24 h. Relative LDH release was used as an index of cytotoxicity. The data were expressed as mean ± SD of three independent experiments. ^# P<0.05, ^## P<0.01, vs. normal group.