Abstract: Objective To observe the impact of Iodixanol against kidney injury molecule-1 and the renal tubular cell apoptosis in rats with renal insufifciency. Methods 48 male wistar rats were randomly divided into four groups:normal control group, model group, Iodixanol group1, Iodixanol group2 (n=12). Iodixanol groups and model group were applied the methods of left renal artery narrowing (30%), right nephrectomy to produce renal insufifciency model in rats respectively, in the preoperative and postoperative 2 weeks every other day by measuring the angular vein blood BUN, SCr and taking urine test of urinary kidney injury molecule-1 (KIM-1) values. After the ifrst three weeks of intravenous saline model group, iodixanol (5 mL/kg)injection of iodixanol group 1, iodixanol (10 mL/kg)injection of iodixanol group 2, the changes of blood urea nitrogen, creatinine and urinary KIM-1 of the two iodixanol groups before applying the contrast agent, after 3 h, 24 h, 48 h, 72 h and 7 d were observed. Three rats of each group were sacriifed in 24 h, 72 h and 7th day after injection of contrast agent. The renal tubular cell apoptosis rates were measured by TUNEL and the differences of each group were compared. Results After in the ifrst two days of surgery, serum BUN, SCr levels in model group were signiifcantly higher than that of the normal group (P<0. 0 1 ) and rised sharply up to about 2 times before surgery, Then gradually decreased after surgery stable at 1.5-2.0 times the preoperative levels two weeks. But the values of KIM-1 were no signiifcant difference (P>0.05). Compared with the model group, in 24 h, 72 h and 7th day after the injection of contrast agents, the values of BUN and SCr, the value of KIM-1 in urine and the rates of apoptosis of renal tubular cells in iodixanol group 2 were signiifcantly increased higher than that of the model group (P<0.01). After three hours iodixanol injection of iodixanol group 2, urinary KIM-1 levels that increased signiifcantly earlier than the rise in the iodixanol group1, the difference was signiifcant (P<0.01). Conclusion By using the left renal artery narrowing and right nephrectomy method can be prepared with mild to moderate chronic renal failure in animal models;iodixanol can cause acute kidney injury of chronic renal failure animals and the speciifc mechanisms may induce renal contrast agent tubule epithelial cell apoptosis. KIM-1 can be used as a contrast agent nephropathy early predictors. Different concentrations of contrast agents for renal tubular injury are different.

Key words: acute kidney injury, kidney injury molecules-1, Iodixanol, tubular injury, wistar rat