Figure 1.

Cytochrome P450 1B1 (Cyp1b1) gene disruption prevents platelet‐derived growth factor‐BB (PDGF‐BB)–induced migration and proliferation of vascular smooth muscle cells (VSMCs) via production of reactive oxygen species. Quantitative analysis of migration of VSMCs expressed as percentage of wound closure after 24 hours of scratch wound healing assay in VSMCs from Cyp1b1 ^+/+ and Cyp1b1 ^−/− mice treated with vehicle or PDGF‐BB (10 ng/mL; A) and VSMCs from Cyp1b1 ^+/+ mice treated with vehicle or PDGF‐BB (10 ng/mL; C) in presence or absence of 4‐hydroxy‐2,2,6,6‐tetramethylpiperidin‐1‐oxyl (Tempol; 2 mmol/L). n=15 (5 scratch wound areas per well for 3 wells) for each treatment condition, for each experiment, with experiments repeated at least 3 times. Quantitative analysis of proliferation (as measured by [³H]‐thymidine uptake) expressed as average fold change from vehicle in VSMCs from Cyp1b1 ^+/+ and Cyp1b1 ^−/− mice treated with vehicle or PDGF‐BB (20 ng/mL; B) and VSMCs from Cyp1b1 ^+/+ mice treated with vehicle or PDGF‐BB (20 ng/mL; D) in presence or absence of Tempol (2 mmol/L). n=6 (6 different wells) for each treatment condition, for each experiment, with experiments repeated at least 3 times. E, Quantitative analysis of H₂O₂ production measured by Amplex Red assay kit and expressed as arbitrary units (A.U.s) of fluorescence intensity in VSMCs from Cyp1b1 ^+/+ mice treated with vehicle or PDGF‐BB (20 ng/mL) in presence or absence of Tempol (2 mmol/L). n=5 for Cyp1b1 ^+/+ group (5 different wells), and n=6 for Cyp1b1 ^−/− group (6 different wells). Data are expressed as mean±SEM. **P<0.01, ****P<0.0001.