Ischemic injury in the cat small intestine: role of superoxide radicals.
Ischemic injury in the cat small intestine: role of superoxide radicals.
复制标题
猫小肠缺血性损伤：超氧自由基的作用。
作者：
D. Parks;G. Bulkley;D. Granger;S. Hamilton;J. McCord
在失血性休克和肠缺血后，在人类和实验动物中已经证明了小肠粘膜的出血性损害。为了明确超氧阴离子自由基和黄嘌呤氧化酶在粘膜损伤发病机制中的作用，我们比较了未处理的猫和用超氧化物歧化酶或别嘌醇预处理的猫在局部降压(肠动脉压=30 mm Hg)3h后所产生的微观粘膜变化。在未经处理的动物中，粘膜的特征是绒毛两侧的大量上皮细胞向上剥离，绒毛完全剥落，最常见的是固有层解体、出血和溃疡。超氧化物歧化酶和别嘌醇预处理均能明显减轻缺血3h引起的绒毛和隐窝上皮细胞的坏死。本研究结果提示，超氧阴离子自由基参与了缺血黏膜损伤的发病机制，黄嘌呤氧化物酶是缺血小肠超氧阴离子自由基的来源。
Hemorrhagic lesions in the small intestinal mucosa have been demonstrated in humans and experimental animals following hemorrhagic shock and intestinal ischemia. In order to define the role of superoxide radicals and xanthine oxidase in the pathogenesis of the mucosal lesions, we compared the microscopic mucosal changes produced by 3 h of regional hypotension (intestinal arterial pressure = 30 mmHg) in untreated cats and cats pretreated with either superoxide dismutase or allopurinol. In the untreated animals the mucosa was characterized by massive epithelial lifting down the sides of the villi, completely denuded villi, and most frequently by disintegration of the lamina propria, hemorrhage, and ulceration. Pretreatment with either superoxide dismutase or allopurinol significantly attenuated the necrosis of villus and crypt epithelium produced by 3 h of ischemia. The results of this study suggest that superoxide radicals are involved in the pathogenesis of ischemic mucosal lesions and that the enzyme xanthine oxidase is the source of superoxide radicals in the ischemic small bowel.