准分子激光术后角膜、房水中SOD、MDA的变化

目的 探讨氧自由基对准分子激光屈光性角膜切削术(PRK)术后角膜及房水的影响。方法 将16只兔右眼行-5.0DPRK。于术后1、3、7、14d测定角膜组织及房水中超氧化物歧化酶(SOD),丙二醛(MDA)的变化,并观察角膜组织病理变化。结果 在术后1、3d角膜SOD活性明显小于对照组(P<0.01),MDA的水平明显高于对照组(P<0.01);但术后房水中SOD、MDA与对照组比较无明显变化(P>0.05)。结论 PRK术后,角膜存在着脂质过氧化形式介导的自由基损害,降低角膜过氧化损伤可以最大程度地减少PRK术后并发症的发生。

The changes of SOD and MDA in cornea and aqueous humour after photorefractive keratectomy

Objective To observe the change of oxygen radical in the cornea tissue and aqueous humour after photorefraclive keratectomy ( PRK ). Methods The activity of superoxide dismutase ( SOD ) was detected with Xanthine Oxidase method. The level of malonaldehyde ( MDA) was determined by Thiobarbituric Acid test. The right eyes of 16 while rabbits underwent PRK to correct 5 diapers of myopia. The left eyes of rabbits served as control. On 1,3,7 and 14 days after surgery,the MDA level and SOD activity in cornea and aqueous humour were respectively measured and hislopathological changes of cornea were observed. Results Aqueous MDA level and SOD activity were nol significant changed after excimer laser ablalion. But significant decrease of SOD activity( P < 0. 01 ) and increase of MDA level( P < 0. 01 ) in cornea were found when compared with the control on 1 ,3 days after PRK. Conclusions These findings suggest that oxygen radicals mediate corneal tissue damage at the form of lipid peroxidation following excimer laser keratectomy in early. Reducing oxidative damage in cornea can minimize tissue damage after PRK.