京尼平交联治疗兔大泡性角膜病变的初步研究

摘要

AIM:To evaluate the effects of genipin cross-linking on bullous keratopathy in rabbits.METHODS:Nine female New Zealand white rabbits with bullous keratopathy were used as an experimental model.They were randomized into three groups.Corneas in Group A (treatment group,n=3) were immersed in 0.25% genipin at 24℃ for 40min;those in Group B (control group,n=3) were immersed in 0.9% sodium chloride solution at 24℃ for 40min;and those in Group C (blank control group,n=3) received no treatment.Follow-up examinations were performed within 2wk after treatment,including slit-lamp microscopy,central corneal thickness (CCT),evaluations of body weight and stress responses,histopathological analyses,and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) for detecting stromal cell apoptosis.RESULTS:Compared to Groups B and C,remission of corneal edema,corneal healing,disappearance of epithelial bullae,a significant decrease in CCT (P<0.05),and a significant increase in body weight (P<0.05) were found in Group A.Animals in Group A became more active and showed less aggression and violent resistance behavior.More regular and dense arrangement of collagen fibers in the corneal stroma and formation of blue strips of cross-linking products were observed in Group A.Cell apoptosis occasionally occurred in the corneal stroma of Group A,while no cell apoptosis was observed in Groups B and C.CONCLUSION:Genipin cross-linking treatment for bullous keratopathy in rabbits results in remission of corneal edema and relief of pain.We hypothesize that genipin cross-linking strengthens collagen fibers in corneal stroma to avoid the formation of corneal edema and bullae.%目的:评价京尼平交联治疗兔大泡性角膜病变的效果.方法:将已建立大泡性角膜病变动物模型的9只雌性新西兰白兔随机分为3组:治疗组(n=3),对照组(n=3),空白对照组(n=3).其中治疗组:刮除角膜上皮后,应用0.25%的京尼平浸泡实验眼角膜40min(24℃);对照组:刮除角膜上皮后,应用生理盐水浸泡实验眼角膜40min(24℃);空白对照组:不进行任何处理.处理后2wk内进行以下检查:裂隙灯检查、中央角膜厚度(CCT)测量、体质量和应激反应评估、组织学检查和利用原位末端转移酶标记技术(TUNEL法)检测基质层细胞凋亡.结果:与对照组和空白对照组相比,治疗组角膜水肿明显减轻、角膜上皮逐渐修复完整、角膜大泡消失、中央角膜角膜厚度显著下降(P<0.05)、体质量显著增加(P<0.05).治疗组的实验动物活动性较处理前增加,反抗行为减少,攻击性减低.治疗组角膜基质层胶原纤维排列更为紧致、规则,可见蓝色条索状交联产物.治疗组角膜基质层均偶见凋亡细胞,对照组及空白对照组未明显见凋亡细胞.结论:京尼平交联治疗可使兔大泡性角膜病变角膜水肿减轻,疼痛症状缓解,其可能的机制为京尼平交联使角膜基质层胶原纤维排列紧密,从而阻止角膜水肿和大泡的形成.