Figure 2.
Effect of VEGF on RANKL expression in murine bone marrow stromal cells and osteoblasts. Serum-starved murine bone marrow stromal cells (A) or MC3T3-E1 murine osteoblast cells (B) were cultured with rhVEGF 100 ng/ml for 2 h. Total RNA was extracted, and RANKL expression was quantified by RT-PCR. (C) MC3T3-E1 murine osteoblast cells were cultured with rhVEGF at different concentrations for 24 h. RANKL protein level was quantified by Western blot analysis. (D) MC3T3-E1 cells were transfected with 1 μg of RANKL/Luc reporter plasmid plus 50 ng of Renilla-luc expression vector. Twenty-four h after transfection, cells were serum starved overnight and then stimulated with rhVEGF 100 ng/ml for 3, 7, and 24 h. Luciferase activity was determined. Results are expressed as relative luciferase activity normalized to Renilla luciferase activity from the transfection control plasmid and represent the mean value ± SE from 3 experiments (P<0.05).