生长抑素对猕猴小肠黏膜浆细胞分泌IgA的影响  

Small intestinal plasma cell function of IgA secretion regulated by somatostatin in macaques with intestinal ischemia-reperfusion

作　　者：谭庆华[1] 范华[1] 吴浩[1] 许兰涛[1] 胡兵[1] 唐承薇[1] 

机构地区：[1]四川大学华西医院消化内科国家生物治疗重点实验室人类疾病相关多肽研究室,四川成都610041

出　　处：《中国药理学通报》2007年第12期1560-1564,共5页Chinese Pharmacological Bulletin

基　　金：国家自然科学基金重点资助项目(No30330270)

摘　　要：目的探讨肠缺血/再灌注(intestinal ischemia reperfu-sion,IIR)时生长抑素(somatostatin,SST)对猕猴小肠浆细胞产生IgA的影响。方法随机将15只猕猴平均分成正常组、IIR及IIR+SST3组。IIR组在失血20%基础上,夹闭肠系膜上动脉1h后恢复血液灌流。测定IIR24h后外周血及小肠黏膜内生长抑素浓度以及小肠组织内IgA、分泌片、浆细胞和肠腔分泌型IgA的水平。IIR+SST组在夹闭肠系膜上动脉前,持续静滴SST5μg.kg-1.h-1,IIR+SST组及正常组(假手术组)其余操作同IIR组。结果①IIR后,外周血及小肠黏膜SST明显减少,而在IIR+SST组明显回升(P<0.05)。②肠黏膜sIgA的水平在IIR组和IIR+SST组之间没有差异,都明显低于正常(P<0.05)。③IIR组黏膜固有层浆细胞较正常明显减少,伴黏膜固有层IgA的锐减(P<0.05),补充SST后浆细胞(P<0.05)和IgA都明显增加(P<0.01)。④黏膜下层浆细胞在IIR组和IIR+SST组都较正常组明显增多(P<0.05),而IgA在IIR后减少(P<0.05),补充SST后明显回升(P<0.01)。结论IIR时,机体内源性SST水平降低,肠道血清型IgA和sIgA均严重匮乏,获得性体液免疫严重受抑;SST可促进IIR时猕猴肠黏膜浆细胞分泌IgA。Aim To investigate the role of somatostatin on plasma cell function of IgA secretion in small intestine of macaques with intestinal ischemia-reperfusion （IIR）. Methods 15 macaques were divided into normal control, IIR and IIR plus SST group. The flow of superior mesenteric artery of macaques in IIR and IIR plus SST group was resumed after one-hour obstruction with a clamp. All 5 maquaces were infused with somatostatin-14 at a dose of 5 g·kg^-1·h^-1 throughout the study in IIR plus SST group. In control group, all animals received the same treatment except IIR operation. Levels of plasma cell, IgA, secretory component, secretory IgA and somatostatin in small intestine were measured using immunohistochemistry, ELISA and RIA methods respectively. Results （ 1 ） The concentrations of SST in peripheral blood and intestinal mucosa were decreased in IIR group in contrast to normal control, and recovered in IIR plus SST group （P 〈 0. 05）. （2） sIgA level of small intestine both in IIR and IIR plus SST group was lower than normal level （P 〈 0. 05 ）. （3）The area of plasma cell positive stain was decreased markedly in lamina propria of IIR group, with a remarkable decreased IOD of IgA in lamina propria （ P 〈 0. 05 ）, in compared with that in normal control and increased in IIR plus SST group （P 〈 0. 05） with a remarkable increased IgA IOD （P 〈 0. 01）. （4）The positive stain area of plasma cell in submucosa both of IIR and IIR plus SST group was larger than that of normal control （ P 〈 0. 05 ）. IOD of IgA in submucosa was decreased （ P 〈 0. 01 ） in IIR group and resumed in IIR plus SST group （P 〈0. 01 ）. Conclusions The severe deficiency of serum IgA and sIgA in small intestine showed a severe suppression of acquired humoral immunity produced by decreased endogenous SST concentration in IIR. SST can improve IgA secretion abihty of plasma cell in small intestinal mucosa in macaques with IIR.

关 键 词：生长抑素 猕猴 肠缺血/再灌注 分泌型IGA 浆细胞 分泌片 

分 类 号：R-332[医药卫生] R322.45