RESUMO
The aim of this study was to establish an efficient and stable mouse model of hyperuricemic nephropathy (HN) by testing different modes of administration of potassium oxonate (PO) combined with hypoxanthine (Hx). Animal welfare and experimental procedures were in accordance with the regulations of the Animal Ethics Committee of Guangdong Pharmaceutical University. Male C57BL/6 mice were randomly divided into a control group, a PO+Hx group (i.g.; 100 mg·kg-1·d-1 and 500 mg·kg-1·d-1, respectively), and a PO+Hx group (i.p.; 100 mg·kg-1·d-1, and 500 mg·kg-1·d-1). This HN model was induced by combination of PO and Hx administration once daily for 21 days. The results of serum biochemistry showed that the levels of serum creatinine and 24 h albuminuria were increased compared with the normal group in intragastric administration of PO combined with Hx (P < 0.05), but there was no significant difference in serum uric acid and hepatic levels of xanthine oxidase. The maximum value of serum uric acid and creatinine was 349.3 μmol·L-1 and 26.4 μmol·L-1, respectively, in mice injected with PO combined with Hx. The levels of liver xanthine oxidase and 24 h albuminuria were significantly increased in mice injected with PO combined with Hx (P < 0.01). Pathological data showed that renal tubules were dilated, the epithelial cells of renal tubules were disordered, and the production of collagen fibers, reactive oxygen species (ROS) and lipid peroxidase 4-hydroxynonenal (4-HNE) were slightly increased after intragastric administration of PO combined with Hx mice. Obvious infiltration of inflammatory cells and large area of collagen deposition, with a large amount of ROS and the lipid peroxide 4-HNE were produced in mice injected with PO combined with Hx. Western blot analysis showed that the expression of fibronectin (FN) and urate transporter 1 (URAT1) was increased after intragastric administration of PO combined with Hx in mice and further increased in mice injected with PO combined with Hx. This study demonstrates that injection with 100 mg·kg-1 potassium oxonate combined with 500 mg·kg-1 hypoxanthine establishes a stable and efficient mouse HN model.