糖尿病大鼠直肠感觉功能减退及其机制  

Impaired Colorectal Sensation in Diabetic Rats and Possible Mechanism

作　　者：乔娴[1] 黄虹[2] 刘劲松[2] 

机构地区：[1]华中科技大学同济医学院附属协和医院神经内科,武汉430022 [2]华中科技大学同济医学院附属协和医院消化内科,武汉430022

出　　处：《华中科技大学学报（医学版）》2010年第4期498-500,505,共4页Acta Medicinae Universitatis Scientiae et Technologiae Huazhong

基　　金：国家自然科学基金资助项目(No.30500233)

摘　　要：目的研究糖尿病大鼠直肠感觉功能的改变及其机制。方法 32只雄性大鼠被分为4组:对照组、糖尿病组、糖尿病+5-HT4受体激动剂组、糖尿病+生理盐水组。通过腹腔注射链脲霉素(STZ)诱导糖尿病大鼠模型,观察大鼠腹壁回撤反射并记录评分(AWR评分)评估结直肠感觉功能。大鼠给予直肠扩张刺激后通过免疫组化的方法检测直肠黏膜层肥大细胞的数量及脊髓后角c-fos阳性细胞数,后两组大鼠在直肠扩张前3 d分别给予5-HT4受体激动剂和生理盐水灌胃。结果①糖尿病大鼠腹壁回撤反射明显低于正常组(P<0.05);②糖尿病大鼠直肠黏膜层肥大细胞阳性率及脊髓后角c-fos阳性细胞数明显低于对照组(均P<0.05);③糖尿病大鼠在给予5-HT4受体激动剂干预后,腹壁回撤反射及脊髓后角c-fos阳性细胞数均显著增加。而生理盐水干预组大鼠腹壁回撤反射及脊髓后角c-fos阳性细胞数与糖尿病组大鼠间差异均无统计学意义(均P>0.05)。结论糖尿病大鼠直肠感觉功能下降,肥大细胞及5-HT4受体可能参与此感觉功能的调控。Objective To investigate the impaired colorectal sensation in diabetic rats and the possible mechanism. Methods Total 32 male rats were divided into 4 groups：control group, diabetic group, diabetic mellitus＋5-HT1 receptor agonist group, and diabetic mellitus ＋ physical saline group. Diabetic rats were induced by streptozocin （STZ）injected intraperitoneally. Colorectal sensation was evaluated by abdominal withdraw reaetion（AWR）. The quantity of mast cells in rectal mucosa and e los positive cells in cornu posterius medullae spinalis were detected by using immunohistochemistry after the rats were given rectal distension stimulation. In the latter two groups, 5 HT4 receptor agonist（tegaserod）or physical saline was administrated for 3 days before the rectal distension respectively. Results ①The AWR in diabetic rats was significantly lower than in control rats（P〈0.05） ;②Positive rate of mast cells in the rectal mucosa and c-fos positive cells in cornu posterius medullae spinalis in diabetic rats were significantly reduced as compared with control group（P〈0.05） ;③After tegaserod was administrated in dia betic rats,AWR and c fos positive cells in cornu posterius medullae spinalis were significantly increased. Conclusion The de creased AWR and c los expression in cornu posterius medullae spinalis suggest that anorectal hyposcnsitivity existed in diabetic rats. Tegaserod can improve this kind of anorectal hyposensitivity,indicating that mast cells and 5-HT1 receptor may contribute to this impaired sensation.

关 键 词：糖尿病 结直肠感觉 肥大细胞 5-HT4受体 

分 类 号：R587.1[医药卫生—内分泌]