急性坏死性胰腺炎肠通透性及病理改变实验观察

目的观察急性坏死性胰腺炎（ＡＮＰ）犬肠通透性变化及肠粘膜病理改变。方法１５只杂种犬,分为ＡＮＰ组（ｎ＝８）和对照组（ｎ＝７）,经主胰管注入牛磺胆酸钠和胰蛋白酶复制ＡＮＰ模型。用气相色谱法检测尿中乳果糖／甘露醇（Ｌ／Ｍ）比值,第７天剖杀,取回肠粘膜作病理观察。结果ＡＮＰ犬尿中Ｌ／Ｍ比值高出对照组２～１０倍。肠粘膜顶端上皮脱落,脱落处有大量细菌侵入,微绒毛部分脱落,面积减少。血浆内毒素水平高出对照组１～２倍,二胺氧化酶活性下降,细菌移位率１００％。结论ＡＮＰ时肠粘膜严重受损,监测尿中Ｌ／Ｍ比值变化可反映早期肠粘膜损伤。     

烧伤合并内毒素血症对肠粘膜的协同损害作用

目的 探讨在Ⅲ度体表烧伤合并小剂量内毒素注射条件下肠粘膜损伤的特点及其发生机理。方法 采用20％Ⅲ度体表烧伤合并小剂量内毒素注射的大鼠模型，动态观察了肠组织血小板激活因子（PAF）、黄嘌呤氧化酶（XO）、丙二醛（MDA）、肿瘤坏死因子（TNFa）及形态学的改变以探讨肠粘膜损害的特点和发生机理。结果 发现烧伤合并内毒素注射后早期肠粘膜即发现－系列显著的病理变化，肠组织PAF、XO、MDA在致伤后大多数时相点显著高于单因素伤组和对照组，肠组织XO、MDA分别与PAF呈显著正相关（P＜0．005）；P＜0．001），在PAF的高峰期，肠粘膜损害更明显。结论 提示烧伤合并内毒素血症对肠粘膜具有明显的协同损害效应，其发生是由于肠粘膜固有细胞激活，导致PAF、TNF产生与释放、XO活化、自由基的产生、脂质过氧化增强。     

阻断肠道淋巴通道对重症急性胰腺炎大鼠肠道细菌易位的影响

目的 从细菌易位途径的角度探讨重症急性胰腺炎(SAP)肠道细菌易位作用的机理.方法 采用胰管内注入5%牛磺胆酸钠溶液诱发大鼠SAP模型,36只Wistar大鼠随机分为假手术组、SAP组和SAP+乳糜管结扎组.每组各12只,于术后16 h剖腹分别抽取下腔静脉血、门静脉血及乳糜管中收集淋巴液,检测其内毒素、肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)的含量,并对肠系膜淋巴结、肺组织、胰腺组织行细菌培养,对肺组织、胰腺组织及末端小肠行病理学检查.结果 诱发SAP 16 h,外周静脉血、淋巴液及门静脉血中内毒素含量均明显升高.同时外周静脉血浆TNF-α、IL-6含量、肠系膜淋巴结、肺组织及胰腺组织细菌培养阳性率亦明显升高,肺损伤及胰腺病理损害严重;乳糜管结扎阻断肠道淋巴通道虽不能阻止SAP所致的肠黏膜病理损害、肠系膜淋巴结细菌易位率及门静脉血内毒素含量,但可显著降低外周血内毒素、TNF-α、IL-6含量.明显减轻肺、胰细菌易位率及其病理损害程度.结论 阻断肠道淋巴通道可减轻SAP时肠道细菌易位所致的高内毒素血症及炎症因子的过表达,改善肺损伤及胰腺病理损害程度.     

大鼠急性坏死性胰腺炎肠黏膜屏障功能障碍的观察

目的: 观察急性坏死性胰腺炎(ANP)大鼠肠黏膜屏障功能的变化。方法: SD大鼠80只随机分为假手术组(n=40)和ANP组(n=40)。胆胰管内逆行注射5%牛磺胆酸钠溶液制作ANP模型。观察大鼠胰腺和回肠的病理变化,动态测定肠脂肪酸结合蛋白(IFABP)、内毒素水平及肠系膜淋巴结和门静脉血细菌移位率。结果: 模型制作后2h血清IFABP明显升高,6h达到峰值(P<0.01),24h后降低。早期内毒素水平有明显升高,48h达到峰值(P<0.01)。肠系膜淋巴结细菌移位在ANP24h后明显升高,48h达到6/8只(P=0.013),门静脉血细菌移位48h达到3/8只(P=0.216)。结论: ANP早期肠黏膜屏障功能受损,引发肠道细菌和内毒素移位,IFABP可能是ANP早期肠黏膜屏障功能受损的预警指标。     

血管紧张素Ⅱ受体拮抗剂对大鼠重症急性胰腺炎的治疗作用

目的探讨血管紧张素Ⅱ(AngⅡ)受体拮抗剂对重症急性胰腺炎(severe acute pancreatitis, SAP)的治疗作用。方法SD大鼠随机分为SAP组、SAP 缬沙坦组和对照组,每组6只。胰管内推注4％牛磺胆酸钠建立SAP动物模型,SAP 缬沙坦组在造模后用灌胃针灌注缬沙坦,对照组仅行假手术。各组术后2 h后观察胰腺病理变化并评分,检测血清淀粉酶(AMY)和胰腺组织髓过氧化物酶(MPO)。结果SAP 缬沙坦组的胰腺病理改变、血清淀粉酶、MPO与SAP组比,均有显著性差异(P<0．05)。结论AngⅡ受体拮抗剂能明显减轻重症急性胰腺炎动物模型的胰腺损伤。     

维生素C对重症急性胰腺炎模型大鼠肠粘膜保护作用的实验研究

目的:①探讨重症急性胰腺炎(SAP)肠粘膜损伤机制;②观察大剂量维生素C对SAP肠粘膜是否有保护作用及其作用机理。方法:选取雄性SD大鼠120只,随机分为3组:SAP模型组、维生素C干预组、正常对照组(n=40)。术后3、6、12、24h分批处死各组动物,检测血浆内毒素、腹水及肠系膜淋巴结细菌易位量、回肠组织丙二醛量;同时观察肠粘膜损伤情况。结果:SAP模型组血浆内毒素、腹水及肠系膜淋巴结细菌易位量明显增高,维生素C干预组上述指标显著下降。结论:SAP模型大鼠肠粘膜屏障作用破坏,肠道细菌易位至腹水及肠系膜淋巴结,血中内毒素明显增加,大剂量维生素C能显著降低细菌易位量及血浆内毒素,对SAP肠粘膜损伤有保护作用。     

蛋白酶体抑制剂MG-132在大鼠重症急性胰腺炎及其肺损伤中的保护作用

目的观察蛋白酶体抑制剂MG-132在大鼠重症急性胰腺炎（SAP）中的保护作用,并探讨其可能机制。方法SD大鼠30只,5％牛磺胆酸钠逆行胆胰管注射制作重症急性胰腺炎（SAP）模型,观察各组大鼠胰腺、肺组织形态学改变,并测定血清淀粉酶及胰腺、肺组织髓过氧化物酶（MPO）活性。结果MG-132治疗组与胰腺炎组及假手术组比较,血清淀粉酶、胰腺及肺组织MPO活性下降（P〈0．05）,组织病理学改变均有不同程度的改善（P〈0．05）。结论制模前30min腹腔注射10mg／kg的MG-132可以明显减轻5％牛磺胆酸钠诱导的大鼠的肺损伤严重程度,并可减轻胰腺炎所致的肺损伤。     

肝创伤时细菌移位及小肠Fas表达的实验研究

目的 研究肝外伤时小肠肠粘膜屏蔽损伤、细菌移位和Fas表达意义。方法 对肝损伤后不同时间进行血中IL－6、TNF、NO、内毒素、肠粘膜通透性的测定以及荧光标记菌示踪、组织学形态学及Fas免疫组化等观察。结果 肝创伤后血中IL－6、TNF、NO升高，内毒素、肠粘膜通透性、荧光标记菌总阳性率均升高；组织学可见损伤，并可见Fas表达的增加。结论 在肝损伤时可引起肠粘膜屏障损伤和细菌移位，肠道是闭合性肝外伤腹腔感染的重要来源。Fas表达增加可能与肠粘膜屏障损伤相关。     

雌激素对创伤失血性休克肠道细菌移位的影响

目的探讨雌激素对创伤失血性休克(Trauma/hemorrhageshock,T/HS)肠粘膜屏障损伤以及肠道细菌移位的影响。方法雌性青春期Wistar大鼠40只,随机分为卵巢切除组10只,对照组10只,雌二醇组10只,大剂量雌二醇组10只,观察T/HS60min,复苏4h后的肠粘膜损伤程度(Chiu氏评分),并取肠系膜淋巴结、肝组织及门静脉血进行细菌培养,改良鲎试剂法测定血浆内毒素含量。结果雌二醇组和大剂量雌二醇组与其他两组相比,肠粘膜Chiu氏评分显著降低,细菌培养计数及内毒素含量明显减少,P均<0.05。结论雌激素能改善创伤失血性休克大鼠的肠粘膜损伤程度,降低肠道细菌及内毒素移位的发生率。     

鱼油对急性重症胰腺炎大鼠肠黏膜屏障的影响

目的:探讨大鼠急性重症胰腺炎(SAP)与肠黏膜屏障的关系以及鱼油干预的影响,为临床营养支持提供依据.方法:用3.5%牛磺胆酸钠逆行胰胆管注射法诱导SAP模型.48只成熟SD大鼠造模成功后分为两组,生理盐水组(A组,n=24),鱼油干预组(F组,n=24),分别于造模后给予尾静脉营养支持,与实验后6、12、24 h分别处死各组的其中8只大鼠,观察各自胰腺、小肠病理变化并测定其血清内毒素浓度.结果:F组门静脉血内毒素水平低于A组(P<0.05);F组肠道损伤评分低于A 组(P<0.05).结论:添加静脉鱼油营养支持能降低SAP时门静脉血中的内毒素水平、促进肠道黏膜的修复、加强肠黏膜屏障的保护作用.     

Effects of platelet activating factor antagonist (BN50739) on gut mucosal injury in acute severe pancreatitis in pigs

Objective To study the role of platelet activating factor (PAF) in the pathogenesis of intestinal mucosal injury and endotoxin/bacterial translocation in acute severe pancreatitis (ASP) in pigs.
Methods ASP was induced by intraductal injection of a mixture of sodium taurocholate and trypsin. BN50739, a specific antagonist of PAF, was given 30 min prior to the induction of ASP. Mucosal blood flow, mucosal myeloperoxidase (MPO) and malondialdehyde (MDA) were determined. Intestinal injury was observed microscopically. Portal blood endotoxin levels and the bacterial counts in the portal blood, intestinal lymph nodes and the pancreas were determined.
Results Prior antagonism of PAF by BN50739 reduced intestinal injury, increased intestinal mucosal blood flow, and reduced blood levels of endotoxin and bacterial counts in the portal blood, mesenteric lymph nodes and pancreas.
Conclusions Intestinal mucosal injury developed in ASP. PAF is responsible for the injury. Antagonism of PAF by BN50739 can improve intestinal microcirculation and reduce the severity of intestinal mucosal injury, which may decrease endotoxin/bacterial translocation.     

Effects of severe acute pancreatitis on gut bacteria/endotoxin translocation in pigs

Objective： To set up a swine model of severe acute pancreatitis（SAP） and to observe its relationship with the gut-originated bacteria/endotoxin translocation. Methods： Forty pigs weighing 17-22 kg were randomly diyided into SAP group （n=34） and sham-SAP group （n=6）. By injecting 1 ml/kg of combined solution of 5% sodium taurocholate and 8 000-10 000 benzoyl arginine ethyl ester（BAEE） units trypsin per milliliter into pancreas via pancreatic duct, SAP was induced under anesthesia. Endotoxin samples from vena cava were determined by chromogenic limulus amebocyte lysate （LAL） technique. Both portal and central vena blood samples were collected before and 72 h after the induction of SAP and cultured for both aerobic and anaerobic bacterial growth. Animals were sacrificed at the end of experiments by injecting 20 ml of 10% KCl intravenously and tissue specimens of mesenteriolum and mesocolon lymph nodes, lung, pulmonary portal lymph nods and pancreas were taken immediately after animal death, and homogenized for bacteriological studies. Results： Systemic plasma endotoxin levels increased rapidly 6 h post induction of SAP（PIS） with a peak at 48 h PIS （P〈0.01）. The magnitude of bacterial translocation in both portal and systemic blood and remote systemic organs as well were recovered PIS. Conclusion： （1） A swine model of SAP was established; （2）The early endotoxemia PIS seamed probable originated from gut endotoxin translocation; （3）The magnitude of bacterial translocation in both portal and systemic blood and the remote systemic organs as well were recovered at 72h PIS.     

Effect of ecoimmunonutrition supports on maintenance of integrity of intestinal mucosal barrier in severe acute pancreatitis in dogs

Background One of the major causes of death in severe acute pancreatitis （SAP） is severe infection owing to bacterial translocation. Some clinical studies suggested that ecoimmunonutrition （EIN） as a new strategy had better treatment effect on SAP patients. But the experiment studies on the precise mechanism of the effect of EIN were less reported. In this study, we mainly investigated the effects of EIN on bacterial translocation in SAP model of dogs. Methods SAP was induced by retrograde infusion of 5% sodium taurocholate into the pancreatic duct in healthy hybrid dogs. The SAP dogs were supported with either parenteral nutrition （PN） or elemental enteral nutrition （EEN） or EIN. The levels of serum amylase, serum aminotransferase and plasma endotoxin were detected before and after pancreatitis induction. On the 7th day after nutrition supports, peritoneal fluid, mesenteric lymph nodes （MLN）, liver, and pancreas were collected for bacterial culture with standard techniques to observe the incidence of bacterial translocation. Pathology changes of pancreas were analyzed by histopathologic grading and scoring of the severity of pancreas, and the degree of intestinal mucosal damage was assessed by measuring mucosal thickness, villus height, and crypt depth of ileum. Results Compared with PN and EEN, EIN significantly decreased the levels of serum amylase, serum aminotransferase, plasma endotoxin, and the incidence of bacterial translocation. Furthermore, compared with the others, the histology scores of inflammation in pancreas and the ileum injury （ileum mocosa thickness, villus height, and crypt depth） were significantly alleviated by EIN （P〈0.05）. Moreover, concerning liver function, the serum levels of alanine aminotransferase, aspartate aminotransferase and albumin were ameliorating significantly in the EIN group. Conclusion Our results suggested that EIN could maintain the integrity of intestinal mucosal barrier and reducing the incidence of bacterial translocation in SAP dogs. Early EIN was safe and more effective treatment for SAP dogs.     

白藜芦醇对重症急性胰腺炎大鼠肠黏膜屏障的保护作用

目的 探讨白藜芦醇对重症急性胰腺炎(SAP)大鼠肠黏膜屏障功能的保护作用. 方法 24只成年雄性SD大鼠随机分为假手术组(SO组)、重症急性胰腺炎组(SAP组)、白黎芦醇治疗组(RES组).各组大鼠均于制模后6 h采集标本.动态浊度法检测血清内毒素含量,TUNEL法检测肠黏膜上皮细胞凋亡率,RT-PCR检测凋亡调控基因Bax、Bcl-2 mRNA表达,激光共聚焦显微镜检测肠黏膜细胞线粒体膜电位变化.结果 RES组血清内毒素水平和肠黏膜细胞凋亡指数均低于SAP组(P<0.01).RES组Bax mRNA表达低于SAP组(P<0.01),Bcl-2 mRNA表达高于SAP组(P<0.01).RES组线粒体膜电位高于SAP组(P<0.01).结论 白藜芦醇可通过抑制肠黏膜上皮细胞凋亡,维持肠黏膜屏障的完整性,从而防止SAP时细菌和内毒素的移居.     

早期腹腔穿刺引流对重症急性胰腺炎大鼠肠道细菌移位的影响

目的 探讨早期腹腔穿刺引流(abdominal paracentesis drainage,APD)对重症急性胰腺炎(severe acute pancreatitis,SAP)大鼠肠道细菌移位的影响.方法 将质粒标记有绿色荧光蛋白的大肠杆菌(E.coli marked with green fluorescent protein,GFP-E.coli)灌饲给SD大鼠,使其成功定植于大鼠肠道.将定植了GFP-E.coli的大鼠分为假手术组(Sham组)、SAP组和APD组,每组12只.逆行胰胆管注射5％牛磺胆酸钠制作大鼠SAP模型.SAP造模后于右下腹留置腹腔引流管,为APD治疗组.造模后24 h无菌条件下取材并处死.对比各组大鼠胰腺组织病理学评分,血液、肠系膜淋巴结(mesentericlymph nodes,MLN)、胰腺组织细菌移位情况,以及血清炎性因子CRP、TNF-α及IL-1β水平.结果 与假手术组比较,SAP组及APD组胰腺组织病理学评分,血液、MLN及胰腺组织细菌移位程度,血清内毒素水平,以及血清炎性因子CRP、TNF-α及IL-1β水平均显著升高(P＜0.05);与SAP组比较,APD组上述各项指标均显著降低(P＜0.05).结论 早期APD能减少SAP大鼠肠道细菌移位及全身炎症水平,并可能因此改善SAP.     

甲状腺素对重症急性胰腺炎大鼠肠黏膜屏障功能的保护作用

[目的]探讨重症急性胰腺炎时甲状腺激素的代谢异常与肠黏膜屏障损伤之间的关系,观察外源性甲状腺激素对肠黏膜屏障的保护作用.[方法]取Wistar大鼠分为假手术对照组、胰腺炎组及甲状腺素组,均应用牛磺胆酸钠制作重症急性胰腺炎模型,腹腔注射给予假手术对照组及胰腺炎组大鼠生理盐水2 mL/kg,给予甲状腺素组大鼠甲状腺素15μg/kg.于给药12 h时检测外周血FT3,FT4,促甲状腺激素和门静脉血内毒素及血清淀粉酶水平,并观察肠黏膜形态学变化.[结果]胰腺炎组大鼠血清FT3,FT4值显著降低,血浆内毒素及血清淀粉酶水平显著升高,肠黏膜损伤评分升高,与假手术对照组比较均有显著性差异;甲状腺素组大鼠内毒素水平与胰腺炎组比较显著降低,血清FT3,FT4值显著升高.[结论]胰腺炎时补充外源性甲状腺素对肠黏膜屏障功能具有保护作用.     

PAF拮抗剂BN50739对大鼠急性肺损伤的作用研究

目的 观察PAF拮抗剂BN50739在治疗烧伤内毒素血症所致的急性肺损伤中的作用，为临床治疗提供依据。方法 采用烧伤复合内毒素血症大鼠模型，于致伤前5min腹腔注射BN50739。动态观察肺病理改变、血气分析、支气管肺泡灌洗液（BALF）中蛋白含量及肺内TNF表达。结果 BN50739可以明显减轻肺水肿，使BALF中蛋白含量明显低于生理盐水对照组，使伤后1.5h和6h血氧分压明显提高。BN50739尚能部分抑制TNF表达。结论 BN50739能部分改善烧伤复合内毒素血症所致的急性肺损伤。     

The protective effect of resveratrol on the intestinal mucosal barrier in rats with severe acute pancreatitis.

BACKGROUND: Severe acute pancreatitis (SAP) can result in intestinal mucosal barrier (IMB) dysfunction. The aim of this study is to demonstrate the protective effect of resveratrol (RES) on the IMB in rats with SAP. MATERIAL/METHODS: Fifty-four male Sprague-Dawley (SD) rats were randomly divided into three equal groups: a sham-operated group (SO), a severe acute pancreatitis group (SAP), and a resveratrol-treated group (RES), each group containing 6 rats which were evaluated at 3, 6, and 12 h. Serum endotoxin levels were determined by turbidimetry. The apoptosis rate of intestinal mucosal cells was detected by using the TUNEL method and the expressions of the apoptosis-related proteins Bcl-2 and Bax were observed using an immunohistochemical technique. RESULTS: The serum endotoxin levels were significantly higher in the SAP group than in the SO group (P<0.05). The endotoxin levels of the RES group were lower than those of the SAP group at all the time-points (P<0.05). In the SAP group, pancreatic and intestinal mucosal congestion, edema, and inflammatory cell infiltration were apparent. In the RES group, pancreatic and intestinal morphological changes were alleviated at all time-points. The apoptotic cell index of the mucosal cells in the RES group was lower than that of the SAP group (P<0.05). In comparison with the SAP group, the RES group's expression of Bcl-2 increased and that of Bax decreased significantly (P<0.05). CONCLUSIONS: An increase in intestinal mucosal cell apoptosis is involved in the intestinal mucosal dysfunction of SAP rats. Resveratrol could decrease endotoxin translocation and protect IMB function.