环氧合酶-2与5-脂氧合酶在溃疡性结肠炎黏膜中的表达及相互关系

Expressions of cyclooxygenase-2 and 5-1ipoxygenase in colonic mucosa of ulcerative colitis and therelationship between them

目的 研究环氧合酶-2（COX-2）和5-脂氧合酶（5-LOX）在溃疡性结肠炎（UC）患者结肠黏膜中的表达及其相互关系.方法 取32例UC患者结肠黏膜标本根据内镜及组织学进行分级,同时收集健康对照者结肠黏膜标本26例.采用实时荧光定量反转录聚合酶链反应（RT-PCR）和免疫组化法检测UC患者结肠黏膜COX-2、5-LOX的mRNA和蛋白表达及其相互关系.结果 32例UC患者内镜分级1级10例、2级19例、3级3例;组织学分级Ⅰ级11例、Ⅱ级17例、Ⅲ级4例.活动期UC组织中COX-2和5-LOX蛋白表达率分别为81.25%和53.13%,正常结肠黏膜COX-2和5-LOX蛋白表达率为11.54%和19.23%,二组比较差异均有统计学意义（P值均＜0.01）.COX-2、5-LOX的阳性表达率与随内镜分级、组织学分级增加而增加;UC患者结肠黏膜炎症组织COX-2和5-LOX mRNA相对含量分别为20.08±1.17和37.83±1.48,结肠黏膜正常组织为48.42±1.69和11.28±1.62,两组差异均有统计学意义（P值均＜0.05）.COX-2与5-LOX的mRNA和蛋白表达呈正相关.结论 COX-2、5-LOX蛋白的表达密切相关,两者均可能在UC发生发展中发挥重要作用.

Objective To investigate the expressions of cyclooxygenase-2 （COX-2） and 5-lipoxygenase （5-LOX） in colonic mucosa of patients with ulcerative colitis （UC）and to analyze the relationship between them. Methods The specimens of colonic mucosa from 32 UC patients were graded according to endoscopic and histological grading standards, and specimens of colonic mucosa from 26 healthy controls were also collected. The expressions of COX-2 and 5-LOX mRNA and protein in colonic mucosa were determined using real-time fluorescent quantitative reverse transcription polymerase chain reaction（RT-PCR） and immunohistochemistry. The correlation between COX-2 and 5-LOX was analyzed. Results For UC patients,10 were class 1, 19 class 2 and 3 class 3 according to endoscopic grading, whereas 19 were class Ⅰ , 9 class Ⅱ and 4 class Ⅲ according to histological grading. The expressions of COX-2 and 5-LOX mRNA in active UC patients were 81. 25% and 53.13%, respectively, and were 11.54% and 19. 23% in healthy controls, respectively, with significant differences between the two groups （all P values〈0.01）. The positive expressions of COX2 and 5-LOX increased in accordance with increasing of endoscopic grading and histological grading.The levels of COX-2 and 5-LOX were 20. 08±1.17 and 37.83 ±1.48 in colonic mucosa tissues of UC patients, respectively, and 48.42 ± 1.69 and 11.28 ± 1.62 in healthy controls, respectively. There was significant difference between the two groups （all P values〈0.05）. A good positive correlation was found between COX-2 and 5-LOX. Conclusions The expressions of COX-2 is closely related to 5-LOX in UC patients. Both may play a pivotal role in inflammation of UC.