Kaçmaz M, Oztürk H S, Karaayvaz M, Güven C, Durak I
Department of Biochemistry, Ibn-I Hospital, Ankara, Turkey.
Can J Surg. 1999 Dec;42(6):427-31.
To establish the antioxidant status of rat intestinal tissues after ischemia-reperfusion and to determine if pretreatment with an allopurinol and antioxidant vitamin combination gives any protection against mucosal injury.
Twenty rats were divided into 4 groups of 5 animals each.
Group 1 (control) rats were not subjected to ischemia-reperfusion and received no allopurinol plus vitamin combination; group 2 rats received vitamins C (200 mg/kg) and E (100 mg/kg) and allopurinol (50 mg/kg) combination daily for 3 days preoperatively; group 3 rats were subjected to ischemia-reperfusion only; and group 4 rats were subjected to ischemia-reperfusion and received the vitamin and allopurinol combination.
Activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) enzymes, the level of thiobarbituric acid-reagent substances (TBARS) and histologic grading of tissue samples.
SOD and GSH-Px activities were decreased, but the CAT activity and TBARS level increased. Pretreatment of the rats with the allopurinol-vitamin C-vitamin E combination did not have any significant effect on the enzyme activities. However, it resulted in important reductions in the TBARS tissue levels. Histologic investigation revealed significant mucosal injury in group 3 rats compared with group 4 rats (mean [and standard deviation] for grading, 4.6 [0.5] versus 1.8 [0.4]).
The enzymatic antioxidant defence system was significantly changed after ischemia-reperfusion and intestinal tissue was exposed to increased oxidant stress, the results of which were peroxidation of some cellular structures and increased concentrations of oxidative products. Although antioxidant treatment did not drastically affect the enzyme activities or afford complete protection of cellular structures against deformation, it apparently could eliminate oxygen radicals and prevent peroxidative reactions.
确定大鼠肠组织缺血再灌注后的抗氧化状态，并判断用别嘌呤醇和抗氧化维生素联合预处理是否能对黏膜损伤起到保护作用。
20只大鼠分为4组，每组5只。
第1组（对照组）大鼠未进行缺血再灌注，未接受别嘌呤醇加维生素联合用药；第2组大鼠在术前3天每天接受维生素C（200毫克/千克）、维生素E（100毫克/千克）和别嘌呤醇（50毫克/千克）联合用药；第3组大鼠仅进行缺血再灌注；第4组大鼠进行缺血再灌注并接受维生素和别嘌呤醇联合用药。
超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）和过氧化氢酶（CAT）的活性，硫代巴比妥酸反应物（TBARS）水平以及组织样本的组织学分级。
SOD和GSH-Px活性降低，但CAT活性和TBARS水平升高。用别嘌呤醇 - 维生素C - 维生素E联合预处理大鼠对酶活性没有显著影响。然而，它使TBARS组织水平显著降低。组织学研究显示，与第4组大鼠相比，第3组大鼠存在明显的黏膜损伤（分级的平均值[和标准差]，分别为4.6 [0.5]和1.8 [0.4]）。
缺血再灌注后酶抗氧化防御系统发生显著变化，肠组织受到的氧化应激增加，结果是一些细胞结构发生过氧化，氧化产物浓度升高。尽管抗氧化治疗并未显著影响酶活性或完全保护细胞结构免于变形，但它显然可以消除氧自由基并防止过氧化反应。
