Inhibitive effect of systemic administration of avastin on retinal neovascularization in rats

Objective To explore inhibitive effect of systemic avastin therapy on retinal neovascularization and the damage of kidney. Methods Sixty 7-day-old SD rats were divided into six groups:air control group(n=10),hyperxia control group(n=10),hyperxia NS group(n=10),avastin groups(high,medium,low dosage groups).SD rats in air control group were not given any treatment.The other fifty rats were put into the environment with 80% oxygen for 5 d to establish models of retinal neovascularization.Then 40 SD rats were given different concentrations of 15.625,31.25,62.5 mg/kg avastin 0.1 ml and NS 0.1 ml in the tail vein in avastin groups and in hyperxia NS group,respectively.The inhibition of angiogenesis was observed by the retinal flat and HE staining,and pathological changes of kidney were observed by HE staining. Results Compared with air control group,there was large retinal new vessels in hyperxia control group,and the density and shape of retinal neovascularization were in disorder.The animal model of oxygen-induced retinopathy with vascular proliferation was successfully established.Compared with hyperxia NS group,retinal new vessels was distributed regularly in avastin treatment groups,its density decreased,and the numbers of the endotheliocyte nuclei of new vessels extending to layer of retina decreased(P0.01).And there was significant difference between the three avastin groups(P0.05).Renal tubular epithelial cell degeneration and necrosis,the basement membrane fracture were found in hyperxia control group,hyperxia NS group.Mild mesangial hyperplasia,interstitial infiltration of inflammatory cells were observed in medium and low dosage groups.The numbers of glomerular cells increased,and stromal cells were mild hyperplasied in high dosage group. Conclusion Systemic avastin therapy could inhibit retinal neovascularization in rats in a dose-dependent manner.The medium and low dosage of avastin could have a mild damage to kidney,but the high dosage could cause more serious injury.