家兔晶状体机械性损伤后虹膜和房水中组织金属蛋白酶抑制物活性的改变

Dynamic changes of tissue inhibitors of metalloproteinases in the rabbit iris and aqueous humor after lens mechanical injury

目的 探讨家兔晶状体机械性损伤后 ,基质金属蛋白酶抑制物 (TIMPs)在虹膜组织和房水中的动态变化及其意义。方法 建立单眼晶状体机械性损伤的家兔模型 ,应用反向酶谱法检测并定量分析损伤后 1、3、7和 15d眼内虹膜组织和房水中两种主要的TIMPs (TIMP 1、2 )的活性 ,并应用蛋白酶谱法检测TIMPs的作用底物基质金属蛋白酶 (MMPs)的活性。结果 健康家兔眼和实验家兔未损伤眼的虹膜组织和房水中 ,均未检测到TIMP 1、2的相应蛋白活性条带。伤后 1d家兔损伤眼的虹膜组织中的TIMP 1、2活性显著增加 (P <0 0 5 ) ,而MMP 2的活性受抑制 ;伤后 1d损伤眼的房水中 ,TIMP 1、2的活性均显著增加 (P <0 0 5 ) ;此后逐渐减少 ,至伤后 7d与健康家兔比较无差异 (P值分别为 0 0 97和 0 777) ;酶谱分析结果显示MMP 2活性的改变与此对应 ,即在损伤后 1d受到抑制 ,此后逐渐恢复。结论 TIMPs参与家兔晶状体机械性损伤后的眼内急性反应 ,对抑制炎性反应、促进创伤修复可能具有重要意义。

Objective To investigate dynamic changes of expression of tissue inhibitors of metalloproteinases (TIMPs) in the rabbit iris and aqueous humor after the lens mechanical injury. Methods Rabbit lens was mechanically injured by a needle through the limbus. Eyes were enucleated on the 1st,3rd,7th and 15th day after injury,the aqueous humor was collected and the iris was isolated. The activity of two main TIMPs ( TIMP-1 and TIMP-2) in the aqueous humor and the iris was assessed by reverse zymography assay while the activity of matrix metalloproteinase-2 (MMP-2) was analyzed by zymography assay. ResultsIn the healthy and uninjured rabbit eye,neither TIMP-1 nor TIMP-2 was detected in the aqueous humor or in the iris. In the iris of the injured eye,the activity of TIMP-1 and TIMP-2 was increased significantly 1 day after the injury ( P < 0.05),the activity of MMP-2 was inhibited. In the aqueous humor of the injured eye,the activity of TIMP-1 and -2 increased significantly ( P < 0.05) 1 day after the injury and the activity of MMP-2 was not detectable. The activity of TIMP-1 and –2 decreased afterwards and no significant difference was detected between the injured eyes and the control eyes 7 days after the injury ( P value was 0.097 and 0.777,respectively),while the activity of MMP-2 was increased gradually. Conclusion TIMPs are involved in the acute inflammation process after the lens injury,which may play an important role in the inhibition of inflammation and in the wound healing. (Chin J Ophthalmol,2004,40:262-265)