The Effects Of Bevacizumab On Corneal Neovascularization In A Rat Model And Its Correlation Between The Drugs Concentration And Effects

Objective: To investigate the effects of Bevacizumab on corneal neovascularization in a rat model and its correlation between the drugs concentration and effects.Methods:1.The rabbits were then divided into two groups: different concentration of bevacizumab(1.25mg/ml,3.75mg/ml,6.25mg/ml,12.5mg/ml,25.0mg/ml)(n=8) was treated with bevacizumab and the other (n=8) treated with saline as control.2. Corneal neovascularization was induced by 1mol/L NaOH in rabbits. The eyes in both groups were examined by slitlamp microscopy for new vessels at 7day. The area of CNV was marked by photography. Immunohistochemistry was used to determine the vascular endothelial growth factor (VEGF) and the matrix metalloproteinase-2(MMP-2) level qualitatively of cornea with SABC method.The expression of VEGF and MMP-2 were examined by immunohistochemis- try and RT-PCR.Results:1.Morphology:In contrast,corneal neovascularization was markedly reduced in eyes receiving subconjunctival injections of bevacizumab as compared to control eyes.Quantitative analysis showed the neovascular response was inhibited markedly in the 6.25mg/ml group and above.2. The area of CNV in control group was larger than bevacizumab group of 6.25mg/ml group and above.(P<0.01).But there were no significant differences between 6.25mg/ml, 12.5mg/ml and 25.0mg/ml(P>0.05).3. Immunohistochemistry showed that VEGF and MMP-2 was decreased expression in corneal stroma. Expression of VEGF and MMP-2 markedly increased in control group while significantly suppressed in bevacizumab group (t<0.01).But there were no significant differences between 6.25mg/ml, 12.5mg/ml and 25.0mg/ml(t>0. 05).4. Expression of VEGF mRNA in control group was higher than bevacizumab group, especially in group of 6.25mg/ml and above. There were no significant differences between 6.25mg/ml, 12.5mg/ml and 25.0mg/ml.Conclusions: Bevacizumab can inhibit corneal neovascularization significantly and the inhibition increased gradually with the drug concentration increase. The inhibition will be stable after the concentration reaches a certain role.