AIM: To establish the mice model of streptozotocin(STZ)-induced proliferative diabetic retinopathy(PDR), and observe the altered expression of some pro-angiogenic molecules such as vascular endothelial growth factor(VEGF)and its receptors(VEGFR1 and VEGFR2), and matrix metalloproteinase(MMP2 and MMP9)during the development of PDR.

METHODS:C57BL/6J mice were intraperitoneal injected with STZ(55 mg/kg)for 5 consecutive days, and blood glucose concentrations were measured after 7d of the injection. The diabetic mice were further housed for 3, 4, 5mo respectively after the development of diabetes. Histological evaluation of retinas was performed. The retinal vessels were detected by immunofluorescence staining with the cluster of differentiation 31(CD31). The mRNA expression of VEGF, VEGFR1, VEGFR2, MMP2 and MMP9 in mice retinas was detected by Real-time PCR analysis.

RESULTS: Retinal histological observation and CD31 staining both demonstrate that there are more vessels in diabetic mice than in normal control mice at 5mo after the development of diabetes. As compared with normal control, the mRNA expression of VEGF, VEGFR1, VEGFR2, MMP2 and MMP9 are all increased in diabetic mice at 5mo after the development of diabetes.

CONCLUSION: This study demonstrates that PDR is occurred at 5mo after the development of diabetes in STZ-induced diabetic mice. In addition, the mRNA expression of VEGF, VEGFR1, VEGFR2, MMP2 and MMP9 are all increased after the development of PDR.