5-HT_(2B)受体表达与腹泻型肠易激综合征患者腹痛的相关性分析

An analysis of correlation between 5-HT_(2B)receptor expression and abdominal pain in patients with diarrhea-predominant irritable bowel syndrome

目的探讨腹泻型肠易激综合征(IBS-D)患者结肠黏膜组织中5-羟色胺2B(5-HT_(2B))受体的表达及其与腹痛的相关性。方法30例IBS-D患者(IBS-D组)和20例健康体检者(对照组)行结肠镜检查并取结肠黏膜组织。采用腹痛症状问卷调查量表进行腹痛严重程度和发作频率评分,HE染色观察结肠黏膜组织学变化,免疫组织化学染色检测5-HT_(2B)受体分布,ELISA法检测5-HT_(2B)受体浓度,qRT-PCR法检测5-HT_(2B)受体mRNA表达,并分析5-HT_(2B)受体浓度与腹痛严重程度和发作频率评分的相关性。结果IBS-D组患者腹痛严重程度和发作频率评分高于对照组(P<0.01)。HE染色结果显示,两组结肠黏膜组织均无明显炎症表现。免疫组织化学染色结果发现,5-HT_(2B)受体阳性表达主要位于结肠黏膜上皮细胞的细胞质及细胞核中,IBS-D组5-HT_(2B)受体阳性表达较对照组明显增多。IBS-D组结肠黏膜组织中5-HT_(2B)受体浓度和mRNA表达高于对照组(P<0.05)。IBS-D组结肠黏膜组织中5-HT_(2B)受体浓度与腹痛严重程度和发作频率评分均呈正相关(r_(s)=0.67和0.72,P<0.01)。结论IBS-D患者腹痛严重程度和发作频率评分与结肠黏膜组织中5-HT_(2B)受体表达呈正相关,提示5-HT_(2B)受体表达上调可能参与IBS-D患者的腹痛发生过程。

Objective To investigate the expression of 5-hydroxytryptamine_(2B)(5-HT_(2B))receptor in the colonic mucosal tissues of the patients with diarrhea-predominant irritable bowel syndrome(IBS-D)and its correlation with the abdominal pain.Methods The colonic mucosal tissues were taken by colonoscopy in 30 patients with IBS-D(group IBS-D)and 20 healthy people(group C).The severity and frequency scores of abdominal pain were evaluated by questionnaire survey scale.The histological change of colonic mucosa was observed by HE staining.The distribution of 5-HT_(2B)receptor was determined by immunohistochemical staining.The concentration of 5-HT_(2B)receptor was measured by ELISA method.The mRNA expression of 5-HT_(2B)receptor was detected by qRT-PCR.And the correlation of 5-HT_(2B)receptor concentration with the severity and frequency scores of abdominal pain was analyzed.Results The severity and frequency scores of abdominal pain in group IBS-D were higher than those in group C(P<0.01).HE staining showed that the inflammatory manifestation was not found in the colonic mucosal tissues of both groups.Immunohistochemical staining revealed that the positive expression of 5-HT_(2B)receptor was mainly expressed in the cytoplasm and nucleus of colonic mucosal epithelial cells,and the positive expression of 5-HTzB receptor in group IBS-D was significantly more than that in group C.The concentration and mRNA expression of 5-HT_(2B)receptor in the colonic mucosal tissues in group IBS-D were higher than those in group C(P<0.05).Moreover,the concentration of 5-HT_(2B)receptor in the colonic mucosal tissues was positively correlated with the severity and frequency scores of abdominal pain in group IBS-D(r_(s)=0.67 and 0.72,P<0.01).Conclusion The severity and frequency scores of abdominal pain in the patients with IBS-D are positively correlated with the expression of 5-HT_(2B)receptor in the colonic mucosal tissues,which indicates that the upregulated expression of 5-HT_(2B)receptor may participate in the development of abdominal pain in the patients with IBS-D.