小牛血清去蛋白眼用凝胶对兔角膜碱烧伤的治疗作用

Therapeutic effect of deproteinised calf serum eye gel on corneal alkali burn

背景角膜化学烧伤，特别是碱烧伤对眼组织造成了严重危害，目前临床上多采用抗炎、抑制免疫反应、角膜移植术等方法进行治疗，但针对角膜碱烧伤微环境下的组织修复研究也十分必要。目的观察角膜修复剂小牛血清去蛋白眼用凝胶对兔角膜碱烧伤的治疗作用。方法采用浸有0．5mol／LNaOH溶液的滤纸贴附于角膜中央的方法制备兔眼角膜碱烧伤模型共24只兔24只眼，采用随机数字表法将模型眼随机分为生理盐水对照组、小牛血清去蛋白眼用凝胶组、空白凝胶基质组、碱性成纤维细胞生长因子（bFGF）阳性对照组4个组，分别采用生理盐水、小牛血清去蛋白眼用凝胶、凝胶空白基质和重组牛bFGF眼用凝胶点眼，每日4次。连续2周。分别于给药前及给药后3、5、7、10、14d于裂隙灯下观察各组眼的角膜溃疡和炎症反应，参照Ando等的评分标准对角膜炎症进行评分，进行角膜上皮荧光素钠染色，记录眼角膜溃疡面积的大小，并参照Trousdale评分标准对角膜溃疡进行评分。于造模后14d用过量麻醉法处死动物并摘除实验眼眼球，对角膜组织行常规组织病理学检查。结果造模后兔眼角膜混浊、水肿、灰白，造模成功率为100％。不同药物点眼后7d，裂隙灯下检查发现生理盐水对照组角膜呈瓷白色混浊，可见前房积脓；小牛血清去蛋白眼用凝胶组角膜溃疡愈合；空白凝胶基质组角膜上皮完整，但眼内结构窥不清；而bFGF阳性对照组角膜溃疡愈合，但可见新生血管。点眼后3、5、7、10、14d，小牛血清去蛋白眼用凝胶组及bFGF阳性对照组眼前节炎症评分均明显低于生理盐水对照组，差异均有统计学意义（P〈O．01）；小牛血清去蛋白眼用凝胶组眼前节炎症评分虽然稍低于bFGF阳性对照组，但二者的差异无统计学意义（P〉0．05）；与空白凝胶基质组相比，小牛血清去蛋白眼用凝胶组各时间点兔眼炎症评分值明显下降，差异均有统计学意义（P〈0．05）。小牛血清去蛋白眼用凝胶组点眼后，角膜溃疡评分均明显下降，与生理盐水对照组相比，角膜溃疡评分的差异有统计学意义（P〈0．01），与bFGF阳性对照组比较，角膜溃疡评分有所下降，但差异无统计学意义（P〉0．05），与空白凝胶基质组比较，角膜溃疡评分明显下降，差异有统计学意义（P〈0．05）。结论小牛血清去蛋白眼用凝胶可减轻家龟角膜碱焙伤的眼前节炎症反应，促进角膜上皮愈合，其疗效优于bFGF。

Background Corneal chemical burns, especially hazards of alkali burn become increasingly prominent. Clinically, anti-inflammatory,immuno-suppression, corneal transplantation are the common treating method for corneal alkali burn. But the research of tissue repair under the microenviroulnent of corneal alkali burn is necessary. Objective The aim of this study was to investigate the therapeutic effect of deproteinised calf serum eye gel on the corneal alkali burn. Methods Alkali burn model of cornea was established on the right eyes by putting the filter paper with 0.5 mol/L NaOH on the center cornea for 1 minute in 24 white rabbits. The model rabbits were divided randomly into 4 groups. Normal saline solution, deproteinised calf serum eye gel, blank matrix gel or recombinant bovine basic fibroblast growth factor（rb-bFGF） eye-gel was topically administered 4 times per day for 14 days in the 4 groups,respectively. The inflammatory reaction was examined under the slit lamp and scored based on Ando＇ s criteria. Corneal fluorescine staining was performed to calculate the corneal ulcer area and scored based on Trousdale＇ s criteria. Histopathological examination of corneas was performed on the fourteenth day after experiment. The use of the experiment animals complied with ARVO Statement. Results Corneal edema and opacification were seen in the model eyes with the modeling successful rate 100%. On the seventh day after experiment, the severe ulcer of cornea and hypopyon appeared in the normal saline solution group. Corneal epithelium was intact but the intrarocular structure was invisible in the blank matrix gel group. In the rb-bFGF group, corneal new vessels were seen, however, the corneal ulcer completely regrow in the deproteinised calf serum eye gel group. In 3,5,7,10 and 14 days after examination,the corneal inflammatory scores were significantly lower in the deproteinised calf serum eye gel group and rb-bFGF group than those of the normal saline solution（ P〈0. 01 ）. No significant difference was found in the inflammatory score between the deproteinised calf serum eye gel group and rb-bFGF group（ P〉0.05 ） but was significantly lower than the blank gel matrix group （ P 〈 0.05 ）. With respect to the corneal ulcer, the score was decreased in the deproteinised calf serum eye gel group compared with the normal saline solution group and blank gel matrix group （P 〈 0.05 ）. However, no significant difference was found in the corneal ulcer score between the deproteinised calf serum eye gel group and rb-bFGF group in various time points （P 〉 0. 05 ）. Conclusions Deproteinised calf serum eye gel can promote the healing of corneal ulcer and remit the inflammatory response after corneal alkali burns with a better effectiveness than rb-bFGF.