Fig. 4

Soluble uric acid stimulates ROS production through URAT1 and p-ERK1/2 in HASMCs. The ROS levels in HASMCs were measured by chemiluminescence. The uric acid-induced production of ROS was mediated by p-ERK1/2 through URAT1 in HASMCs. A and B Uric acid stimulated ROS production in HASMCs, but transfection of URAT1 siRNA decreased the effect of uric acid on ROS production. C and D The MEK inhibitor PD98059 decreased the inducing effect of uric acid on ROS production. ROS: reactive oxygen species; URAT1: urate transporter 1; p-ERK1/2: phospho-extracellular signal-regulated kinase 1/2; HASMCs: human aortic smooth muscle cells; MEK: mitogen-activated protein kinase kinase. The upper and lower whiskers show the maximal and minimal values, respectively, and the upper, middle and lower horizontal lines in the box represent the upper, middle and lower quartiles, respectively. *P < 0.05