羊膜移植对急性碱烧伤角膜中MMP-9及TIMP-1表达的影响

目的 :探讨羊膜移植对角膜碱烧伤后基质金属蛋白酶 (MMP 9)及其抑制剂 (TIMP 1)在小鼠角膜中的表达影响及意义。方法 :将 4 0只昆明小鼠随机分为实验组和对照组 ,采用 1mol·L-1氢氧化钠溶液烧伤小鼠角膜 ,建立炎症性角膜碱烧伤动物模型 ;对实验组小鼠右眼角膜行羊膜移植术 ;对照组不行羊膜移植。然后在羊膜移植术后第 2 ,7,14 ,2 1d处死动物。用免疫组织化学染色方法和计算机图像分析系统检测小鼠角膜烧伤后基质金属蛋白酶在角膜中的分布及其平均光度值。结果 :在对照组 ,角膜中MMP 9在第 2d出现表达 ,第 7d达高峰 ,以后逐渐降低。TIMP 1开始表达不明显 ,第 7d出现表达 ,14d达高峰 ,以后逐渐降低。羊膜移植组各时间点MMP 9表达低于对照组 ,而TIMP 1表达高于对照组。结论 :羊膜移植术可通过调节基质金属蛋白酶及其抑制剂的表达平衡 ,从而抑制和延迟碱烧伤后角膜融解的发生和发展。

Expression of Matrix Metalloproteinase-9 and Tissue Inhibitor of Metalloproteinase-1 in Acute Alkali-burned Mouse Model with Amniotic Membrane Transplantation

Objective: To study the expression and role of matrix metalloproteinase-9(MMP-9)and its tissue inhibitor (TIMP-1) in mice with alkali burned after amniotic membrane transplantation. Methods: Forty KM mice were divided into two groups and burned with alkali. Amniotic membrane transplantation (AMT) was performed in AM group. At different time points (2,7,14,21days) after AMT, the expressions of MMP-9 and TIMP-1 in corneal were detected immunohistochemically, and the results were analyzed by computer medical image analysis system. Results: In control group, MMP-9 and TIMP-1 were expressed in the epithelial cells and stromal and exudated inflammatory cells. The level of MMP-9 elevated from the 2nd day, peaked on the 7th day, then dropped afterwards. TIMP-1 was expressed on the 7th day, reached peaks on the 14th day, and decreased gradually to the base-line level. At the same time-point, the level of MMP-9 in AM group was greatly lower than that in control group, while the level of TIMP-1 AM group was greatly higher than that in control group. Conclusion: Immediate intervention for acute alkali burns with amniotic membrane transplantation promotes wound healing and inhibits the development of cornea melting by adjusting the proportion of matrix metalloproteinase and its tissue inhibitor by epithelium and inflammatory cells.