【作者】 李大生；

【导师】 张小霓；

【作者基本信息】 福建医科大学 ， 麻醉学， 2010， 硕士

【摘要】 目的建立大鼠小肠缺血与再灌注模型,通过观察肠脂肪酸结合蛋白和丙二醛含量变化,结合小肠组织病理学改变,探讨异丙酚处理对大鼠小肠缺血与再灌注损伤的影响,为临床研究提供实验参数和依据。方法成年健康SD雄性大鼠30只,体重250～300g。随机分为对照组(C组)、小肠缺血与再灌注组(I/R组)和异丙酚处理组(R组),每组l0只。通过夹闭肠系膜上动脉(SMA)制作小肠缺血与再灌注损伤模型。对照组仅在无菌条件下打开腹腔,不夹闭SMA;I/R组沿腹中线打开腹腔,游离肠系膜上动脉根部,用无损伤动脉夹夹闭SMA 60min,然后松开动脉夹行再灌注60min;R组在夹闭SMA前10min给予异丙酚10mg/kg静脉注射,随后按10mg/(kg·h)维持处理。各组分别于缺血前、缺血后15、30、60 min和去除无损伤动脉夹再灌注后30、60 min采集静脉血用于检测肠脂肪酸结合蛋白(I-FABP)。最后取空肠组织5cm,用于检测丙二醛(MDA)含量及常规制备全层石蜡切片行HE染色,光镜下观察小肠组织病理学变化。结果C组肠脂肪酸结合蛋白(I-FABP)水平在整个实验过程中变化不明显,保持在较低水平;I/R组和R组I-FABP水平在缺血15 min后可迅速达到缺血前数十倍,缺血30 min后可达到高峰,再灌注30 min后下降,但再灌注60min后仍为缺血前的数十倍;R组I-FABP水平与I/R组比较在缺血及再灌注期间内明显降低,两组比较存在着显著差异(P<0.01)。与C组相比,I/R和R组小肠组织MDA含量均明显升高(P<0.01);与I/R组相比,R组小肠组织MDA含量降低,两组比较差异具有显著性(P<0.05)。小肠组织病理学结果:C组小肠未见明显组织学异常改变;I/R组可见小肠粘膜层上皮和大部分腺体坏死,粘膜固有层血管扩张充血,组织水肿,其间有较多的炎症细胞浸润。R组小肠损伤程度较I/R组明显减轻。结论1、静脉异丙酚处理可以降低大鼠小肠缺血与再灌注损伤后血清I-FABP水平和小肠组织MDA含量,明显减轻光镜下小肠组织病理学损伤程度。2、静脉异丙酚处理对大鼠小肠缺血与再灌注损伤有较好的保护作用。3、异丙酚处理对大鼠小肠缺血与再灌注损伤的保护机制可能与改善小肠粘膜血液循环病理生理学机制及抑制缺血与再灌注氧自由基的生成有关。更多还原

【Abstract】 Objective To set up a rat model of intestinal ischemia and reperfusion(I/R).To evaluate the changes of intestinal fatty acid binding protein (I-FABP),and Malondialdehyde(MDA),and the morphological changes of intestinal mucosa To investigate the effect of propofol on gut injury following intestinal ischemia and reperfusion,and to provide the basic experimental parameters and evidences.Methods Thirty major adult male Sprague-Dawley(SD) rats (weighting250～300g) were randomly divided into 3(n=10 each):control group(C); Ischemia and Reperfusion group (I/R);propofol group(R).A rat model of intestinal ischemia and perfusion was stablished by blocking the superior mesenteric artery(SMA) with clap for 60 min followed by 60 min reperfusion. Group C rats underwent only midline laparotomy without blocking superior mesemteric artery.Group I/R and R rats underwent a midline laparotomy and then SMA isolation (with a microvascular clip).The SMA occlusion lasted for 60 minutes followed by 60 minutes of reperfusion.Group R rats underwent a additional administration of propofol(10mg/kg) 10min before ischemia and followed by continuous infusion at 10mg/(kg·h). Blood samples were collected from the inferior vena cava prior to ligation、15、30、60 minutes after ligation and 30、60 minutes after reperfusion for determination of I-FABP.The animals were all killed at the end of 1h reperfusion and a small segment of ileum was taken for determination of MDA.The ileum slices were made and pathological changes were also observed under microscope in each group.Results In group C,the level of I-FABP had no significant difference and keep at a low level during the operation time.In group I/R and group R the level of I-FABP increased 15 minutes after ligation and peaked at 30 minutes.It dropped after 30 minutes of reperfusion.But at 60 minutes after I/R injury,it was number of times of the nomlal serum level of I-FABP.Compare with group I/R,the I-FABP in group R decreased during the period of ligation and reperfusion and there was significant difference between the Group I/R and R (P<0.01).The MDA concentrations in group I/R and group R were significantly higher than those in group C (P<0.01) during the period of ligation and reperfusion.The MDA concentrations in group R were lower than those in group I/R (P<0.05).The morphological changes of intestinal tissues were observed with light microscopy.With the staining of HE, In group C,it cannot be seen abnormality in small intestinal tissue.In group I/R the morphological changes of intestinal mucosa could be observed.The mucous layer appeared necrotic,some intestinal mucosal cells shed to enteric cavity,and submucous layer had hyperemia and edema obviously.In group R the necrosis of intestinal mucosa was ameliorated and damage was not obvious as compared with the group I/R.Conclusion Administration with propofo1 can reduce the level of I-FABPand MDA and attenuate the injury of intestinal mucosa in rats after intestinal ischemia and reperfusion injury.Administration with propofo1 can provide significant protection against intestinal ischemia and reperfusion injury,which may be attributed to the ameliorative blood circulation effect and antioxidant effect of propofo1.更多还原