Tube formation of retinal microvascular endothelial cells is inhibited by the blocking of NLRP3. (A) The tube formation was markedly enhanced in the HG group of HRMECs and was inhibited by blocking of NLRP3. Then, the (B) tube meshes, (C) nodes and (D) tube length were counted, and the results revealed that the HRMECs in the HG group formed more meshes and nodes than the control; the tube total length in the HG group was higher than that in the control group. However, after the blocking of NLRP3, the tube meshes, nodes and tube length were reduced compared with the HG group. *P<0.05 and **P<0.01 compared with the control; #P<0.05 and ##P<0.01 compared with the relative HG-induced HRMEC cell group. NLRP3, NLR family pyrin domain containing 3; HG, high glucose; HRMECs, human retinal microvascular endothelial cells.