摘要
目的研究结构和诱生型一氧化氮合酶(iNOS和eNOS)在大鼠胃溃疡模型中的表达和活性变化,以探讨它们在溃疡病理中的表达规律及所起的作用.方法采用乙酸胃腔内注射方法制备大鼠胃溃疡模型,采集溃疡诱导后1 h～15 d的溃疡基底、边缘和正常胃组织标本,采用RT-PCR方法和Westernblot方法测定组织中iNOS和eNOS的nRNA表达及蛋白水平,采用测定组织匀浆液转化L[3H]-精氨酸成L-[3H]一瓜氨酸的能力的方法检测标本的总NOS和iNOS活性.结果乙酸诱导的大鼠胃溃疡模型溃疡基底在1 d～3 d出现自限性的iNOS的高表达和活性,这一时间与炎症高峰出现时间相一致,正常胃组织检测不到iNOS的表达,溃疡愈合期的iNOS表达和活性较低.eNOS的表达和活性水平在整个过程中相对稳定.结论机体在损伤后能够自限性诱导和调节iNOS的表达,而主要来源于iNOS活性的NO在胃溃疡的损伤和炎症到愈合的病理过程中起到重要作用.
AIM To study the expression and activity patterns of constitutive and inducible forms of nitric oxide synthase (eNOS and iNOS) in gastric ulcer and their roles in gastric ulcer healing. METHODS Rat models of gastric ulcer were induced by intraluminal application of acetic acid solution, Stomach samples from the base, margin and normal tissues around the gastric ulcers were collected at different times after ulcer induction. Expressions of eNOS and iNOS mRNA and their protein levels were detected by RT-PCR and Western Blot methods. NOS activities were measured as the ability of tissue homogenates to convert L-[~3H]-arginine to L-[~3H] citrulline. RESULTS A high level of expression and enzyme activity of iNOS were detected in the ulcer base in day 1 to day 3 after ulcer induction when the tissue inflammation was most severe. The protein level and activity of iNOS in normal gastric tissue or the ulcerated tissue in the healing phase were undetectable or at a low level. The expression and activity of eNOS was relatively stable during the whole experimental period. CONCLUSION There are restricted induction and regulation of iNOS expression and activity in the healing process of gastric ulcer. Nitric oxide mainly derived from the activity of iNOS, plays an important role in the pathological process of inflammation and gastric ulcer healing.
出处
《世界华人消化杂志》
CAS
2001年第3期288-292,共5页
World Chinese Journal of Digestology
关键词
胃溃疡
病理学
一氧化氮合酶
生物合成
一氧化氮合酶
代谢
疾病模型
stomach ulcer/pathology
nitric oxide synthase/biosynthesis
nitric oxide synthase/metabolism
disease models, animal
