NOX4 and cardiac hypertrophy: Our previous research demonstrated that Nox4 promoted cardiac hypertrophy via activating the ROS‐ADAM17 pathway in primary cardiomyocytes stimulated with 100 nmol/L Ang II for 24 hours.11 Therefore, rutaecarpine inhibits the Nox4‐ROS‐ADAM17 pathway in primary cardiomyocytes treated with Ang II.