Vascular endothelial injury is closely related to the progression of various cardio-cerebrovascular diseases. Whether Human Urinary Kallidinogenase (HUK) has a protective effect on endothelial injury remains unclear. This study established an in vivo model of rat common carotid artery intima injury and an in vitro model of human umbilical vein endothelial cell (HUVECs) injury induced by hydrogen peroxide (H