H₂O₂ was used to injure African green monkey renal epithelial cells (Vero). The injury degree of Vero cells was characterized by detecting the cell survival rate, the concentration change of superoxide dismutase (SOD) in culture medium, the release of malondialdehyde (MDA) and the change of expression quantity of osteopontin (OPN) on cellular surface. The injured degree of Vero cells by H₂O₂ was time-dependent and concentration-dependent. After injured, the release quantity of MDA increased, the concentration of SOD decreased and the expression quantity of OPN increased significantly, thus resulting in an increase of the adherent quantity of crystals. The modulation of cells before and after injury to the growth of calcium oxalate (CaOxa) crystals was investigated by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The CaOxa crystals induced by the cells in control group contained simultaneously calcium oxalate monohydrate (COM) and dihydrate (COD) crystals, and these crystals had obtuse edges and corners. However, the crystals induced by the cells in injured group were mainly COM crystals, and they had irregular shape with sharp edges and corners. Consequently, the risk of CaOxa stones formation increased after the cells were injured. The oxidative injury model of Vero cells established in this paper was in favor of understanding the formation mechanism of calcium oxalate stones in cell level.

Key words: biomineralization, calcium oxalate, cell modulation, oxidative damage