褪黑素对脊髓缺血-再灌注损伤的抗氧化作用

Protective Effect of Melatonin on Experimental Spinal Cord Ischemia-Reperfusion Injury

目的:观察褪黑素对脊髓缺血-再灌注损伤的保护作用。方法:SD大鼠随机分为3组,一组仅行剖腹术,不钳夹动脉。另二组行缺血-再灌注术。分别在再灌注前后各5min腹腔注射褪黑素和含2%乙醇的生理盐水。4h后取腰骶段脊髓,测量组织中的丙二醛、过氧化氢酶和谷胱甘肽过氧化物酶。结果:再灌注后4h,对照组组织中丙二醛显著升高,过氧化物酶和谷胱甘肽过氧化物酶活性降低,褪黑素组与对照组相比组织中丙二醛水平明显降低,而过氧化氢酶和谷胱甘肽过氧化物酶活性增加。结论:运用外源性褪黑素能明显减轻脊髓缺血-再灌注后的氧化损伤。

Objective To observe the protective of melatonin on experimental spial cordischemia-reperfusion injury. Methods Male Spryue-Dwleys rats were divided into three groups, rats inone group only had laparotomy without aortic occlusion; in other two groups had their infrarenal arota temporarily occluded for 30 min, then were given either a 20 mg/kg single dose of melatonin and saline containing 2% ethanol intraperitoneally twice, 5 min fefore aortic occlusion and 5 min after the clamp was removed. At 4hours after reperfusion, the animals were authanized and lumboscaral spinal cord tissue was removed for the determination tissular malondialdehyde（MDA） levels and relevant enzyme activities. Results Malondialdedhyde levels,indicating the shem-operated group. Catalase （CAT） and glutathione peroxidase（GSH- Px） enzyme activities were decreased in the the nonmelatonin treated group compared to the sham-operated group. Melatonin can attenuate the changes（P〈0.05）. Conclusion Melatonin can effectively protected spinal cord from ischemiareperfuion injury.