摘要目的 研究缺血后处理(ischemic postconditioning,IPo)抗大鼠肠缺血-再灌注(intestinal ischemic/reperfusion injury,IL/R)损伤后肠黏膜的蛋白质变化,探讨其可能的肠保护机制.方法 16只雄性SD大鼠,随机分为IL/R组和IPo组.IL/R组阻断肠系膜上动脉60 min后再开放60min,IPo组在阻断肠系膜上动脉60 min后行三个循环灌注30 s/,阻断30 s,余同IL/R组.再灌注结束即刻在距回肠末端5 cm处取20 cm小肠刮取肠黏膜,利用高分辨双向电泳对肠黏膜组织进行蛋白质分离,Image Master 2D Elite 5.0图像软件进行分析,应用基质辅助电离解析飞行时间质谱获取肽质量指纹图谱,检索数据库鉴定差异表达的蛋白质,明确其生物学功能.结果 研究发现10个差异表达的蛋白质点,其中6个在IPo组中表达上调,4个表达下调.9个通过鉴定及功能分析,其中醛糖还原酶、醛脱氢酶与抗氧化应激和抑制凋亡相关.结论 建立了重复性较好的IPo与IL/R损伤后肠黏膜组织的双向电泳图谱.IPo的肠保护机制可能与其上调醛糖还原酶和醛脱氢酶的表达,从而抑制氧化损伤及细胞凋亡有关.

abstractsObjective To investigate the changes of proteins expressions in intestinal mucosa of rats after is chemic postconditioning (IPo) against intestinal ischemic/reperfusion (Ⅱ/R) injury of intestine in order to elucidate its potential mechanisms of protective role. Methods Sixteen SD rats were randomly divided into Ⅱ/R group and IPo group ( n = 8). Rats of both groups received an episode of ischemic/reperfusion insult to intstine that was made by occlusion of the superior mesenteric artery (SMA) for 60 minutes. Rats of IPo group underwent three additional episodes of clamping SMA on for 30 seconds and off for 30 seconds successively after prolonged reperfusion/reperfusion of intestine. The intestinal mucosa was taken by scratching immediately after reperfusion in both groups, and total proteins were separated by immobilized pH gradient (IPG) based two-dimensional gel electrophoresis (2-DE). The differentially expressed proteins were analyzed using Image Master 2D Elite 5.0 image analysis software, and the proteins were cut out from the gel and then identified using MALDI-TOF-MS. The biological information of these proteins was looked for in the database of these peptide mass finger-printing (PMF) .Results Ten differentially expressed proteins were found, of which 6 were up-regulated and 4 were down-regulated in IPo group. Nine proteins were identified and characterized by their bioelements including aldose reductase and aldehyde dehydrogenase that were related to anti-oxidative stress and inhibition of cell apoptosis. Conclusions The well-reproducible 2-DE profiles of intestinal mucosa in II/R and IPo groups were established. The potentially protective effects of IPo may be attributed to up-regulating protein expressions of aldose reductase and aldehyde dehydrogenase, and thereby suppressing oxidative stress and cell apoptosis.