SSTR1和SSTR2在肠易激综合征和活动期溃疡性结肠炎患者结肠黏膜中的表达及其临床意义

生长抑素是胃肠道重要神经递质之一，其功能的发挥是由生长抑素受体（SSTR）介导的，SSTR表达水平与多种胃肠道疾病有关。目的：研究SSTR1、SSTR2在肠易激综合征（IBS）和活动期溃疡性结肠炎（UC）患者结肠黏膜中的表达及其临床意义。方法：收集腹泻型IBS（IBS—D）、便秘型IBS（IBS—C）、活动期UC患者和正常对照者各30例，记录患者的症状发生时间、严重程度并评分。以免疫组化方法检测活检结肠黏膜中SSTR1、SSTR2的表达。结果：SSTR1、SSTR2的表达位于上皮组织的上皮细胞和间质淋巴细胞的细胞膜和细胞核中。正常结肠黏膜组织中两者均为弱阳性表达，IBS组和UC组SSTR2表达阳性率和免疫组化评分显著高于正常对照组（P〈0．05）。各组中SSTR1、SSTR2免疫组化评分均呈线性正相关（P〈0．05）。SSTR1、SSTR2的表达与IBS—D的腹泻病程和程度以及UC的便血程度相关（P〈0．05），SSTR2的表达与IBS-C的便秘病程和程度相关（P〈0．05）。结论：SSTR1、SSTR2在正常结肠黏膜中为弱阳性表达．两者在IBS和UC的发病中起有一定作用。UC与IBS—D在发病机制上可能存在一定关联。

Expressions and Clinical Significances of SSTR1 and SSTR2 in Colonic Mucosa of Patients with Irritable Bowel Syndrome and Active Ulcerative Colitis

Background： Somatostatin is one of the important enteric neurotransmitters in human gut, and its action is considered to be mediated via specific somatostatin receptors （SSTRs）. It has been reported that the expression levels of SSTRs are correlated with the pathogenesis of various gastrointestinal diseases. Aims： To investigate the expressions and clinical significances of SSTR1 and SSTR2 in colonic mucosa of patients with irritable bowel syndrome （IBS） and active ulcerative colitis （UC）. Methods： Thirty diarrhea predominant IBS （IBS-D） patients, 30 constipation predominant IBS （IBS-C） patients, 30 active UC patients and 30 normal controls were enrolled. The time course and severity of symptoms of IBS and UC were recorded and scored. Expressions of SSTR1 and SSTR2 in biopsied colonic mucosa were determined immunohistochemically. Results： Expressions of SSTR1 and SSTR2 were mainly located in the membrane and nucleus of epithelial cells and interstitial lymphocytes. They were weakly expressed in normal colonic mucosal tissues. The positivity rate and immunohistochemical score of SSTR2 in IBS and UC groups were significantly higher than those in the normal controls （P〈0.05）. A positive linear correlation in immunohistochemical scores between SSTR1 and SSTR2 was observed in all these four groups （P〈0.05）. The expressions of SSTR1 and SSTR2 were correlated with the time course and severity of diarrhea in IBS-D group and with the severity of hematochezia in UC group （P〈0.05）, while the expression of SSTR2 was correlated with the time course and severity of constipation in IBS-C group （P〈0.05）. Conclusions： Expressions of SSTRI and SSTR2 are weakly positive in normal colonic mucosa. They might play a role in the pathogenesis of IBS and UC, and there might be some correlations between UC and IBS-D in their pathogenic mechanisms.