Avastin不同给药途径对兔角膜新生血管及超微结构的影响

Effect of different administrations of Avastin on corneal neovascularization and ultrastructure in rabbit

目的研究阿瓦斯汀不同给药途径对兔角膜新生血管及超微结构的影响。方法健康新西兰大白兔50只,随机选取48只兔左眼制作碱烧伤角膜新生血管动物模型,造模成功后随机分为局部滴眼组(A组)、结膜下注射组(B组)、角膜基质注射组(C组)和模型对照组(D组),每组12只,未造模2只兔双眼为空白对照,于碱烧伤后第1天、第4天、第11天、第18天、第32天观察兔眼结膜充血、角膜混浊、新生血管生长情况,并进行眼前节照相,同时计算各实验兔眼角膜新生血管面积;第11天、第18天、第32天每组各处死4只兔,即刻抽取左眼房水检测血管内皮生长因子(vascular endothelial growth factor,VEGF)含量,取新生血管生长最旺盛的角膜组织分别固定,待做电镜、免疫组织化学等检测。结果角膜新生血管在碱烧伤后11d内生长迅速,第18天时有所消退,第32天时趋于相对稳定,A组、B组、C组角膜新生血管面积与D组在各个时间点之间比较,差异均有统计学意义(均为P<0.05)。碱烧伤后各时间点房水中VEGF浓度均高于正常水平,碱烧伤后11d内房水中VEGF浓度逐渐升高,至第18天时达到高峰,第32天时有所下降并趋于较稳定的水平。CD31在正常兔眼角膜组织中未见表达,A组、B组、C组阳性细胞数明显少于D组,差异均有统计学意义(均为P<0.05)。A组、B组、D组角膜超微结构在第11天、第18天、第32天时除碱烧伤损伤外无明显其他改变,在第18天、第32天时C组角膜超微结构损伤重于A组、B组、D组。结论局部滴眼、结膜下注射、角膜基质注射三种给药途径均对角膜新生血管有较好的抑制作用。局部滴眼与结膜下注射给药途径简单安全、效果稳定,未见对角膜超微结构产生明显影响;角膜基质注射虽短期效果显著,但对角膜超微结构产生了较明显的影响。

Objective To explore the effect of different administrations of Avastin on corneal neovascularization and ultrastructure in rabbit.Methods Fifty healthy adult New Zealand white rabbit were used,50 rabbits were selected to establish animal model of corneal neovascularization with alkali burn in the left eye,then randomly divided into local eye dropping group（group A）,subconjunctival injection group（group B）,corneal stroma injection group（group C） and model control group（group D）,12 cases in each group,the dual eyes of the other two rabbits was set as blank control.The conjunctival congestion,corneal opacity and neovascularization were observed at 1 day,4 days,11 days,18 days and 32 days after alkali burn,the anterior segment was pictured,and the area of corneal neovascularization was calculated.Each 4 rabbits were sacrificed at 11 days,18 days and 32 days after alkali burn,the content of vascular endothelial growth factor（VEGF） in aqueous humor was detected,and the corneal tissue with the most growth neovascularization was fixed and detected by transmission election microscope and immunohistochemistry.Results The corneal neovascularization grew rapidly within 11 days after alkali burn,slowed at 18 days,then stabled at 32 days,there were statistical differences in area of corneal neovascularization at each time point between group D and group A,B,C（all P0.05）.The extent of VEGF in aqueous humor at each time point was more than normal level,the VEGF concentration gradually increased within 11 days after alkali burn,reached the peak at 18 days,then decreased slightly and stabled at 32 days.No CD31 expressed in normal corneal tissue,the number of positive CD31 cells in group A,B,C were obviously less than that in group D,there were statistical differences（all P0.05）.There was no obviously change of corneal ultrastructure at 11 days,18 days and 32 days in group A,B and D except for burning damage,which in group C at 18 days and 32 days were more severe than group A,B and D.Conclusion Three administrations have better inhibitive effect on corneal neovascularization.Eye dropping and subconjunctival injection are safe and effective with no effect on corneal ultrastructure,and the effect of corneal stroma injection in short time is markedly,but also has obvious effect on corneal ultrastructure.