MAPK3 and cardiac hypertrophy: In this research, we discovered that rutaecarpine alleviated hypertensive cardiac hypertrophy in AAC‐induced hypertensive rats, that rutaecarpine suppressed Ang II‐induced cardiac hypertrophy and that rutaecarpine inhibited the Nox4‐ROS‐ADAM17 pathway and over‐active ERK1/2 pathway in hypertrophic cardiomyocytes.