Methods and Results:The expression of interleukin-1β (IL-1β) increased significantly following cuff placement compared with mice with carotid artery ligation alone. IPH occurred in the cuff-placed carotid artery following treatment with the negative control (NC) small interfering RNA (siRNA). However, the occurrence was significantly reduced in the cuff-placed carotid artery following treatment with an IL-1β siRNA. Neovessel formation was significantly reduced in the carotid artery treated with the NC siRNA compared with that treated with IL-1β siRNA. IL-1β significantly inhibited the tube formation and wound healing capacities of vascular endothelial cells in vitro. Furthermore, immunostaining of matrix metalloproteinase-9 (MMP-9) significantly increased in the carotid artery treated with the NC siRNA compared with that treated with IL-1β siRNA.