NOS3 and hyperuricemia: It has been found that hyperuricemia can induce human umbilical vein endothelial cell apoptosis and endothelial dysfunction through endothelial nitric oxide synthase (eNOS) phosphorylation and endoplasmic reticulum stress, reducing eNOS activity and nitric oxide production, activating NF-κB, and increasing the levels of inflammatory cytokines (20, 21).