Effect Of Shuangdan Mingmu Capsule On Expression Of Retinal VEGF-a,VEGF-b,VEGF-c And Its Receptor Flk-1 Of Diabetic Retinopathy Rat Model

Object:To observe the effect of Shuangdan Mingmu Capsule?SDMMC?on expression of retinal VEGF-a,VEGF-b,VEGF-c and its receptor Flk-1 of diabetic retinopathy rat model.Method:40 male SD rats were divided into 4 group randomly including blank group A,model group B,SDMMC group C,positive control group D,10 rats in each group?20 eyes?.the diabetic retinopathy rat model of B,C,D three groups were induced by streptozotocin?STZ?in 50mg/kg single dose intravenous injection.After 72h tail vein blood was taken,Blood glucose was measured in Johnson blood glucose meter.The urine glucose was measured in tes-tape.When rats'fasting blood glucose concentration was more than 16.7mmol/L and urine glucose was above+++,they would be diagnosed to diabetic rats.After modeling,they was observed for 1w and the stability was successful.After modeling for 1w,they were done continuous intragastric administration.After intragastric administration at 4^thW and 8^thW,each group were sacrificed at half animal?5 rats?.Morphology of retinal tissue was observed in light microscope and electron microscope and the expression of VEGF-a in retinal tissue,VEGF-b,VEGF-c and its receptor Flk-1 were checked in immunohistochemistry.Results:?1?After taking medicine at 4^thWand 8^thW,compared with the model group,theretinal morphology and ultrastructure of SDMMC group and positive control group were significantly improved,the structure was clear,only part of tissue edema,mild hyperplasia of the capillary endothelial cells.The model group showed the retinal tissue edema,capillary wall thickening,endothelial cell proliferation and fibrous tissue hyperplasia.The ultrastructure showed that the retinal capillary endothelial cells of model group were obviously swollen,the cells became round,the mitochondria swelled and became vacuolated,basement membrane was thickening.?2?Immunohistochemical results:After taking medicine at 4^th week,8^th week,average gray values of VEGF-a,VEGF-b,VEGF-c and its receptor Flk-1 protein expressions of model group,SDMMC group and positive control group were lower than those of the normal group.Compared with normal group,model group had significant difference?P<0.01?.Average gray values of VEGF-a,VEGF-b,VEGF-c and its receptor Flk-1 protein expressions of SDMMC group and positive control group were higher than those of model group.There was significant difference?P<0.05 or 0.01?.Compared with positive control group,SDMMC had no significant difference?P>0.05?.Compared with these indexes at 4^th week,average gray values of model group,SDMMC group and positive control group at 8^th week increased,but there was no significant difference?P>0.05?.?3?After taking medicine at 4^th week,8^th week,average optical values of VEGF-a protein expressions of model group,SDMMC group and positive control group were higher than that of the normal group.Compared with normal group,model group had significant difference?P<0.01?.Average optical values of VEGF-a,VEGF-b,VEGF-c and its receptor Flk-1 protein expressions of SDMMC group and positive control group were lower than those of model group.There was significant difference?P<0.05 or 0.01?.This showed after the SDMMC and positive control drug were used,rat retinal VEGF-a,VEGF-b,VEGF-c and its receptor Flk-1 expression was down-regulated markedly.Compared with positive control group,SDMMC had no significant difference?P>0.05?.Compared with these indexes at 4^th week,average optical values of model group,SDMMC group and positive control group at 8^th week decreased,but there was no significant difference?P>0.05?.Conclusion:?1?Diabetic rats model was successfully induced by streptozotocin?STZ?at a dose of 50mg/kg intravenous injection in rats'tail.?2?Diabetic retinopathy rat model showed retinal edema,capillary wall thickening,endothelial cell proliferation,fibrous tissue hyperplasia.And the expression of VEGF-a,VEGF-b,VEGF-c and its receptor Flk-1 in the retina were significantly increased.?3?SDMMC could obviously improve retinal morphology and ultrastructure of the diabetic retinopathy rat model.?4?SDMMC could significantly improve the average gray value of VEGF-a,VEGF-b,VEGF-c and its receptor Flk-1 expression in retina of diabetic retinopathy rat model,reduce the average optical density value which indicated SDMMC could significantly reduce the expression of VEGF-a,VEGF-b,VEGF-c and its receptor Flk-1 in the retina,had certain protective effect on retina of diabetic retinopathy rat.