羊膜移植对大鼠角膜碱烧伤后基质金属蛋白酶的影响

目的探讨羊膜移植对大鼠角膜中度碱烧伤后角膜上皮细胞和基质成纤维细胞中基质金属蛋白酶(matrix metalloproteinase，MMP)变化的影响。方法将12只SD大鼠随机分成2组，每组6只，分别作为碱烧伤后1d组和14d组。在2组中，所有大鼠角膜建立中度碱烧伤模型，左眼行羊膜移植，右眼作为对照。应用免疫组化法，分别观察碱烧伤后1d和14d实验组与对照组中MMP-9和MMP-2表达的变化。结果碱烧伤后1d，实验组与对照组中，角膜上皮细胞内的MMP-9和MMP-2的表达与正常角膜上皮细胞内的MMP-9和MMP-2的表达相比明显升高，但两组间的表达差异无显著性；而2组成纤维细胞内的MMP-9和MMP-2的表达与正常成纤维细胞内的MMP-9和MMP-2的表达相比明显升高，两组间的表达差异无显著性。碱烧伤后14d，2组中角膜上皮细胞内的MMP-9和MMP-2的表达与碱烧伤后1d情况相似，两组间的表达差异无显著性；2组成纤维细胞内的MMP-9和MMP-2的表达与碱烧伤后1d组相比明显升高，并且实验组中的MMP-9和MMP-2的表达与对照组相比也有明显升高。结论碱烧伤后大鼠角膜上皮细胞和基质成纤维细胞中的MMP-9和MMP-2的表达都有升高。羊膜移植能增强MMP-9和MMP-2在成纤维细胞中的表达，提示羊膜在加快角膜碱烧伤后的重塑中起一定作用。

The effect of amniotic membrane transplantation on matrix metalloproteinase after alkali burns of the corneas in SD rats

Objective To investigate the effects of amniotic membrane transplantation on the matrix metalloproteinase in corneal epithelia and corneal fibroblasts after moderate alkali burn of the corneas in SD rats.Methods Twelve SD rats were randomly divided into two groups (experimental group and control group), each consisting of 6 rats. Models of moderate corneal alkali burn were established in all rats, then the left eyes received amniotic membrane transplants and the right eyes served as controls. After 1 day and 14 days, matrix metalloproteinase expression in the corneal tissue was observed by immunohistochemistry.Results On the 1st day, expression of matrix metalloproteinase (MMP-9 and MMP-2) in the corneal epithelia or corneal fibroblasts of the two groups was higher than expression in normal corneal epithelia or fibroblasts, but the difference between the two groups was not statistically significant. On the 14th day, expression of MMP-9 and MMP-2 in the corneal epithelia of the two groups was the same as that for the 1st day, and the difference between the two groups was not statistically significant. Expression of MMP-9 and MMP-2 in the corneal fibroblasts of the two groups was greater than expression on the 1st day, while expression of MMP-9 and MMP-2 in the experimental group was higher than that for the control group.Conclusion It was found that MMP-9 and MMP-2 in corneal epithelia or corneal fibroblasts could up-regulate after alkali burns of the corneas. Amniotic membrane transplantation can enhance the expressions of MMP-2 and MMP-9 in corneal fibroblasts. This suggests that the amniotic membrane plays a role in remodeling the cornea after alkali burn.