壳聚糖对胃溃疡大鼠血清中ＭＤＡ、ＳＯＤ及ＧＳＨ－ＰＸ的影响

瞿春莹　李定国　汪余勤　陈梅梅

摘 要 目的：观察壳聚糖对大鼠消化性溃疡愈合的影响，探讨其抗溃疡的可能机制。方法：采用冰乙酸胃窦部浆膜下注射法制备大鼠消化性溃疡模型。70只实验大鼠被随机分成7组，即假手术对照组、模型对照组、泮托拉唑治疗组、硫糖铝混悬液治疗组及3个不同剂量壳聚糖治疗组（ 0.25 g/kg,0.5 g/kg,1.0 g/kg）。按Guth标准记分判定溃疡指数并计算溃疡抑制率；HE染色观察组织结构。采用羟胺法测定超氧化物岐化酶(SOD)，DTNB法测定谷胱甘肽-过氧化物酶(GSH-Px)，TAB法测定丙二醛(MDA)。结果：壳聚糖治疗组与模型对照组比较，溃疡指数明显降低，溃疡抑制率升高（P < 0.01)；1.0 g/kg壳聚糖治疗组大鼠血清SOD、MDA、GSH-Px值与模型对照组均有显著性差异（P<0.05）； 0.25 g/kg壳聚糖治疗组及0.5 g/kg壳聚糖治疗组大鼠血清MDA值与模型对照组比较均有显著性差异（P< 0.05），但SOD、GSH-Px值与模型对照组比较均无显著性差异。结论：壳聚糖可促进冰乙酸溃疡大鼠的溃疡愈合，并呈一定的量效关系。其促进溃疡愈合作用可能与抗氧化机制有关。

关键词 胃溃疡 壳聚糖 抗氧化作用

中图分类号：R97 文献标识码：B 文章编号：1006-1533(2008)05-0219-04

Effect of chitosan on the serum levels of MDA, SOD, and GSH-Px in rats with gastric ulcer

Qu Chunying, Li Dingguo, Wang Yuqin, Chen Meimei

(Xinhua Hospital of Medical Instite of Shanghai Jiaotong University, Shanghai，200092)

ABSTRACT Aim:

To observe the effect of chitosan on the healing of gastric ulcer and explore the possible mechanisms for its action. Methods: Glacial acetic acid was subserosally injected to the gastric antrum of rats to establish the animal model of gastric ulcer. Seventy rats were randomly divided into 7 groups: sham-operated group, model group, pantoprazole-treated group, sucralfate-treated group, and three chitosan-treated groups at low, moderate and high doses (0.25, 0.5, and 1.0 g/kg). The ulcer index was evaluated by Guth method and the inhibition ratio of ulcer formation was calculated. The morphological changes were observed by HE staining. The levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px),and malondialdehyde (MDA) were determined by hydroxylamine method, DTNB method and TAB method respectively. Results: The ulcer index was significantly decreased and the inhibition ratio of ulcer formation was significantly increased in chitosan-treated groups compared with model group (P<0.01). The serum levels of MDA, SOD and GSH-Px in chitosan 1.0 g/kg group had significant difference compared with those of model group (P<0.05). The serum level of MDA in chitosan 0.25 g/kg group and 0.5 g/kg group were significantly different with that of model group (P<0.05), but there was no significant difference in the serum levels of SOD and GSH-Px among chitosan 0.25 g/kg group and 0.5 g/kg groups and model group. Conclusion: Chitosan may improve the healing of gastric ulcer induced by glacial acetic acid in rats. The effect was in a dose-dependent manner. The action mechanism of chitosan may be related with its antioxidant activities.

KEY WORDS Ulcer; Chitosan; Antioxidant activity

消化性溃疡是一类常见病、多发病。随着药物治疗的进展，消化性溃疡的愈合率也日趋提高，但不能避免复发。

壳聚糖由甲壳素加工而成，对人体安全无毒［1～3］，可生物降解，具有良好的生物相容性。壳聚糖的水解产物是表皮细胞或组织生长必需的生物活性物质，有利于溃疡局部肉芽组织和新生血管的形成；壳聚糖分子中含有极性基团并带正电荷，溶解于胃酸，形成黏稠的胶，附着在胃壁上形成一层保护膜，阻止胃酸和胃蛋白酶对溃疡面的腐蚀，促进溃疡修复和愈合。国内外动物实验证实［4～9］，壳聚糖有保护胃黏膜、促进胃溃疡愈合作用。本文对壳聚糖抗溃疡的可能机制作一研究。

1 材料与方法

1.1 材料

动物：雄性Sprague-Dawley系大鼠，体重190～250 g，共70只，购自西普尔-必凯实验动物有限公司。

药物：壳聚糖，脱乙酰度92%，华东理工大学提供；泮托拉唑钠肠溶片，沈阳东宇药业有限公司生产；硫糖铝混悬液，上海旭东海普药业有限公司生产。

试剂：超氧化物歧化酶(superoxide dismutase,SOD)测试盒、丙二醛(malonaldehyde,MDA) 测试盒及谷肽甘肽-过氧化物酶 (glutathione peroxidase ，GSH-Px) 测试盒，均购自南京建成生物工程研究所。