Protective effects of glucagon-like peptide 2 on intestinal ischemia-reperfusion rats

Our objective was to evaluate the protective effects of glucagon-like peptide 2 (GLP-2) on intestinal ischemia/reperfusion (I/R) rats. Thirty-two rats were randomly assigned to four experimental groups, each of 8: Group A, sham rats underwent laparotomy only, without superior mesenteric artery (SMA) occlusion; Group B, I/R animals underwent laparotomy and occlusion of the SMA for 60 minutes followed by 120 minutes of reperfusion; Group C, I/R animals underwent intestinal I/R, and received pretreatment with GLP-2 for 3 days preoperatively; and Group D, I/R animals underwent intestinal I/R, received pretreatment with GLP-2 as above, and during the reperfusion phase were injected intravenously with GLP-2. After the reperfusion of intestinal ischemia, samples of intestinal mucosa, mesenteric lymph nodes (MLN) and blood were prepared for determination. In the pretreatment rats with GLP-2 (group C), Chiu's scores, bacterial colony counts, serum D-lactate, intestinal mucosal MDA and ET-1, and serum endotoxin, TNF-alpha and IL-6 were significantly reduced compared with intestinal I/R rats (group B). Administration of GLP-2 during the reperfusion phase following pretreatment (group D) showed further protective effects in comparison with the pretreatment rats (group C). We conclude that treatment with GLP-2 attenuates intestinal I/R injury, reduces bacterial translocation, inhibits the release of oxygen free radicals and ET-1, and may well inhibit the production of proinflammatory cytokines.     

原位肝移植大鼠肠道微生态状况研究

目的 探讨肝移植术后大鼠肠道微生态的变化.方法 将雄性Brown-Norway(BN)大鼠40只随机分成肝移植组(BN→BN,n=16,共8对)、模拟移植组(n=8)、假手术组(n=8)和对照组(n=8),24 h后处死,分析肠道菌群构成、回肠末端超微结构变化、血浆内毒素水平以及细菌易位至肝、脾、肾和肠系膜淋巴结的比例.结果 肝移植术后24 h存在明显的肠道菌群紊乱,表现为肠杆菌科细菌和肠球菌数量增加(P<0.05),乳杆菌和双歧杆菌数量下降(P<0.05),移植组与模拟移植组存在肠黏膜上皮细胞微绒毛的损伤;肝移植组血浆内毒素水平升高(P<0.01),细菌易位至肝脏、脾脏和肠系膜淋巴结的阳性率增加(P值均<0.05);与模拟移植组比较,肝移植组细菌易位至肝脏的阳性率增加(P<0.05).结论 肝移植术后存在一定程度的肠道微生态紊乱和肠道屏障功能损伤,可能与肝移植手术过程中所经历的缺血再灌注过程有关.     

Detection of intestinal bacterial translocation in subclinical ischemia-reperfusion using the polymerase chain reaction technique

BACKGROUND/PURPOSE: The purpose of this study was to evaluate the detection of bacterial translocation after subclinical ischemia reperfusion injuries in rats with the polymerase chain reaction (PCR) technique. METHODS: Six-week-old weaning rats were divided into 3 groups. (1) Experiment rats (n = 20) were gavaged with 10(10) Escherichia coli followed by superior mesentery artery occluded for 10 minutes, then reperfused for 30 minutes. (2) Control rats (n = 20) received bacterial gavage. (3) Group 3 were sham rats (n = 20). After the procedure, 3 mL of blood was obtained from the portal vein. The terminal ileum and mesenteric lymph node (MLN) near the terminal ileum were removed. E. coli DNA was detected in blood and MLN samples by PCR, and histological changes were examined. RESULTS: E. coli DNA detection in ischemia-reperfusion (I/R) group animals was 6 of 20 (30%) in the MLN and 2 of 20 (10%) in the blood. PCR was negative in all the rats in the control group and in the sham group (P < .05). There were no significant differences in the histological examination of rat intestines. CONCLUSION: These data suggest that subclinical intestinal I/R injury results in bacterial translocation. Also, PCR is a highly sensitive and rapid method to detect the presence of microbial DNA.     

大鼠脊髓损伤致截瘫后肠道细菌移位的实验研究

目的：探讨大鼠脊髓损伤致截瘫后是否发生肠道细菌移位。方法：建立大鼠脊髓损伤性截瘫模型，以脊髓损伤性截瘫后12h、24h、48h大白鼠为实验组，未损伤脊髓的正常大白鼠为对照组。在无菌条件下，采集动物下腔静脉血进行内毒素定量测定和细菌培养，采集肝、脾、肠系膜淋巴结、肠腔内容物作细菌培养并进行菌种鉴定。取实验组和对照组各动物的肝、脾、肠系膜淋巴结、空肠、回肠进行病理切片HE染色检查，取空、回肠进行电镜检查。结果：大鼠脊髓损伤致截瘫后24h开始出现内毒素血症，截瘫后48h出现细菌移位。结论：大鼠脊髓损伤致截瘫后将发生肠道细菌移位，提示脊髓损伤截瘫的病人应尽早给予抗生素治疗。     

Melatonin reduces bacterial translocation after intestinal ischemia-reperfusion injury

Melatonin, the primary pineal hormone, has been reported to protect from oxidative injury after ischemia-reperfusion (IR). The aim of this study was to evaluate the effects of exogenous melatonin on intestinal integrity, ileal colonization, and bacterial translocation 45-minute after mesenteric IR. Sixteen male ACI rats randomly divided into two groups underwent 45-minutes intestinal ischemia by clamping the superior mesenteric artery. One hour prior to ischemia, study animals (n=8, group A) were treated with melatonin (10 mg/kg IP) while control animals (n=8, group B) received the same volume of saline solution. An additional six animals underwent laparotomy and served as a sham-operated group. Animals were sacrificed 24 hours after reperfusion; peritoneal swabs and biopsies of liver, spleen, lung, mesenteric lymph nodes, cecum, and terminal ileum were obtained for microbiology. The ileum samples were also processed for histopathological evaluation of IR-induced injury. Twenty-four hours after reperfusion bacterial translocation to the peritoneal cavity present in all group B animals was reduced to 37.5% among those that were melatonin-treated (group A; P <.05). Furthermore bacterial translocation to mesenteric lymph nodes, spleen, and liver was significantly lower in group A than group B (P <.05). Although cecal and ileal counts did not differ between the two groups, ileal counts from control animals showed increased colonization. Accordingly, a single injection of exogenous melatonin significantly reduced the intestinal IR injury and prevented bacterial translocation.     

Intestinal permeability and bacterial translocation following small bowel transplantation in the rat

In addition to its role in absorbing nutrients, the intestinal mucosa provides an important barrier against toxins and bacteria in the bowel lumen. The present study evaluated gut barrier function following orthotopic (in continuity) intestinal grafting in rats. Graft histology, intestinal permeability, and bacterial translocation to the grafted mesenteric lymph nodes, the host's liver, and the host's spleen were assessed on the 3rd, 5th, and 7th postoperative days. The study group received no immunosuppression after allotransplantation. The two control groups included rats with isografts and rats with cyclosporine-treated allografts. On the 7th POD, the study animals had moderate transmural inflammation due to rejection, with normal histology in the isografts and CsA-treated allografts; increased intestinal permeability, measured by urinary excretion of oral 51Cr-EDTA (P less than 0.01); and increased number of bacteria in the MLN and spleen (P less than 0.05). The number of bacteria in the MLN and spleen of the study group positively correlated with the changes in intestinal permeability (P less than 0.05). Rejection of the orthotopic intestinal graft leads to increased intestinal permeability and bacterial translocation from the lumen of the graft to the host's reticuloendothelial system. Measures to improve gut barrier function and antibiotic therapy during rejection episodes may help reduce the incidence of septic complications after intestinal grafting.     

Effects of ursodeoxycholic acid,glutamine and polyclonal immunoglobulins on bacterial translocation in common bile duct ligated rats

Background: The present study was conducted to investigate the effects of ursodeoxycholic acid (UDCA), glutamine and i.v. polyclonal immunoglobulins (IVIG) on the bacterial translocation (BT) and intestinal integrity of obstructive jaundice (OJ) in an animal model. Methods: Fifty rats were randomized into five groups containing 10 rats each. All procedures were performed aseptically under general anaesthesia using intramuscular ketamine (25 mg/kg). The abdomen was opened and the common bile duct was identified, mobilized, doubly ligated using 5−0 silk and divided. In group 1 (the ‘sham’ group), the rats had a similar incision followed by mobilization of the common bile duct (CBD), without ligation or division. In group 2 rats, only common bile duct ligation (CBDL) was performed. In group 3, CBDL was performed and UDCA was administered by orogastric intubation once daily. In group 4 rats, CBDL was performed and glutamine was given by orogastric intubation once daily. Therapeutic substances were started orally on the day CBDL was fulfilled and were continued for 7 days. In group 5, IVIG was administrated via a femoral vein catheter just before CBDL. The animals were killed at the end of the 7th day, and serum levels of total bilirubin (TB), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and gamma-glutamyl transpeptidase (GGT) were measured. Mesenteric lymph nodes (MLN), liver, spleen and blood were cultured. The terminal ileum specimens were examined histopathologically. Results: Bacterial translocation significantly increased in the MLN and spleen of rats in group 2 as compared to groups 3, 4 and 5 (P < 0.05, P = 0.001, P = 0.001, respectively). The BT of the liver in group 2 was significantly higher than that of group 5 (P < 0.05). In the blood, the BT was significantly higher in group 2 than groups 3, 4 and 5 (P < 0.05). The bacterial counts, colony-forming units per gram tissue (cfu/g), were found significantly higher in MLN, liver and spleen of rats in group 2 than those of groups 3, 4 and 5 (P = 0.000). The average villus height in the group 4 was significantly higher than that of groups 2, 3 and 5 (P = 0.000). Conclusion: The present experimental study has demonstrated that the administration of glutamine, UDCA and IVIG reduce the incidence of BT and additionally glutamine preserves intestinal mucosal integrity.     

Bacterial translocation, endotoxaemia and apoptosis following Pringle manoeuvre in rats

BACKGROUND: Intraoperative occlusion of the hepatoduodenal ligament (Pringle manoeuvre (Pm)) is often employed for the reduction of blood loss during liver surgery. No data exist to date on the effects of Pm on mucosal barrier dysfunction, systemic bacterial translocation (BT), endotoxaemia and apoptosis. MATERIALS AND METHODS: Sixty-five male Wistar rats in three groups: I (n=25) controls, II (n=20) sham operation, III (n=20) occlusion of the hepatoduodenal ligament (Pm). Tissue samples from mesenteric lymph nodes (MLNs), liver, lungs and spleen were analysed after 30 min and at 24 h. Endotoxin was measured in portal and aortic blood and routine haematological and biochemical parameters were measured before and after Pm. RESULTS: No differences were found in the blood parameters before and after Pm, but a significant increase in contaminated MLNs and liver was noted. All cultured bacteria were enteric in origin. Portal and aortic endotoxin were significantly increased. Overall the ileal architecture remained intact in all specimens studied and no significant pathology was observed. The ABC increased after Pm significantly (P<0.01). CONCLUSION: Normothermic Pm of 30 min duration results in immediate and delayed gut barrier failure by significantly increasing BT and endotoxaemia which might be attributed to portal stasis leading to intestinal congestion as well as temporary liver ischaemia. Apoptosis increased significantly 30 min after performing the Pm.     

Glucan and glutamine reduce bacterial translocation in rats subjected to intestinal ischemia-reperfusion.

Intestinal ischemia/reperfusion (I/R) may induce bacterial translocation (BT). Glutamine (GLN)-enriched nutrition decreases BT. However, little is known about the effect of glucan (GL) in BT. This study investigated the combined effect of GL/GLN on BT, intestinal damage, and portal blood cytokines in animals under I/R. Four groups of 10 rats each were subjected to 60 min of intestinal ischemia and 120 min of reperfusion. The control group (group 1) received only rat food/water, group 2 received glutamine via gavage, group 3 received subcutaneuos soluble (1, 3)-d-glucan, and group 4 received GL + GLN. A sham group (group 5) served as a normal control. Bacterial cultures of ileum, mesenteric lymph nodes (MLN), liver and lung biopsies, histological changes of ileum, and serum cytokines variables were examined after I/R. Data were analyzed by analysis of variance (ANOVA) and the Newman-Keuls test. Results showed that GLN, GL, and GL/GLN significantly reduced BT to MLN, liver, and lung. BT was more attenuated after GL treatment than GLN (P < .05). Rats treated with both GL and GLN exhibited lower bacterial colony counts than the ones treated only with GLN or GL. Severe mucosal damage on histological findings was shown in group 1, but these findings were significantly ameliorated (P < .05) in groups 3 and 4. Tumor necrosis factor (TNF)-a and interleukin (IL)-6 levels in portal serum were significantly reduced and IL-10 was increased by GL and GLN treatment. In conclusion, the use of GL was more effective than GLN in reducing BT, intestinal damage, and cytokine levels after I/R. Additionally, the combination of GL and GLN improved results.     

大鼠门静脉高压症及梗阻性黄疸时细菌移位与黄嘌呤脱氢酶和黄嘌呤氧化酶的关系

目的探讨大鼠门静脉高压症（porta; ju[ertemsopm,PH）及梗阻性黄疸（obstructive jaundioe,OJ）时,细菌移位（bacterial translocation,BT）与黄嘌呤氧化酶（xanthine oxidase,XO）、黄嘌呤脱氢酶（xanthine dehydrogenase,XD）之间的关系。方法将雄性SD大鼠60只随机分为对照组（A组）,胆总管结扎组（B组）和门静脉缩窄组（C组）,每组20只。术后第3周取肠系膜淋巴结、脾、肝组织及门静脉、腔静脉血细菌培养,测定门静脉压力（free portal pressure,FPP）,及肠XO,XD活性水平。结果B组及C组细菌移位率明显高于对照组（P〈0．01）,对照组为12％,B组和C组分别为28％和54％;B组和C组空肠XO水平活性明显高于对照组（P〈0．01）,B组和C组门静脉压力也较对照组升高。细菌移位率与XO活性成正相关（r=0．603）。XD活性水平无显著差异。结论门静脉高压症及梗阻性黄疸时可发生细菌移位,可能与肠黏膜屏障被破坏通透性增强有关,肠壁XO水平活性增强引起肠黏膜屏障通透性增高有助于细菌移位发生。     

肠道缺血再灌注损伤时肠淋巴干结扎对系统炎性反应的影响

目的比较大鼠肠道缺血再灌注损伤时肠淋巴干结扎与不结扎对循环中炎性介质和细菌内毒素的影响。方法采用肠道缺血再灌注模型进行肠系膜淋巴管结扎。大鼠随机分4组，每组10只：空白组（A组）；假手术组（B组）；肠道缺血再灌注组（C组）；肠道缺血再灌注加淋巴干结扎组（D组）。缺血再灌注后，作肠系膜淋巴结培养计算细菌易位率；检测循环中内毒素、D-乳酸、二胺氧化酶、TNF—α、IL-1β、IL-6和sICAM-1水平。结果细菌易位率A、B两组为0；C组40％，D组20％。与A、B组比较，C、D两组内毒素、D-乳酸和二胺氧化酶水平显著增高（P〈0．05），且D组显著低于C组；血循环中各细胞因子除sICAM-1在D组与C组之间没有显著差异外，C组的IL-1β、IL-6和TNF-α浓度均明显高于D组（P〈0．05）。结论肠道缺血再灌注损伤时，肠淋巴干结扎可减少细菌在肠系膜淋巴结的定植，并减轻肠道缺血再灌注的损伤及增加通透性，从而减轻全身炎性反应。     

Prolonged continuous or intermittent vascular inflow occlusion during hemihepatectomy in pigs

OBJECTIVE: To assess ischemia and reperfusion (I/R) injury in a hemihepatectomy model in pigs after prolonged continuous or intermittent vascular inflow occlusion in the liver. SUMMARY BACKGROUND DATA: Massive intraoperative blood loss during liver resections can be prevented by temporary vascular inflow occlusion, consequently leading to ischemia and reperfusion injury in the remnant liver. Previously, in a pig liver resection model in which only limited I/R injury was induced during brief (90 min) vascular inflow occlusion, the authors demonstrated reduced I/R injury after continuous (CNT) occlusion, compared to intermittent (INT). This liver resection study on pigs was undertaken to assess I/R injury after prolonged (120 min) CNT or INT occlusion. METHODS: In pigs (37.0 +/- 1.5 kg), liver ischemia during 2 hours was CNT (n = 6) or INT (n = 6) (eight subsequent periods of 12 min ischemia and 3 min recirculation), followed by 6 hours of reperfusion. A left hemihepatectomy (45.5% +/- 1.4%) was performed within the first 12 minutes of ischemia. No hepatic pedicle clamping or liver resection was performed in control experiments (n = 6). Microvascular damage was assessed by hyaluronic acid (HA) uptake capacity of the liver (parameter of early sinusoidal endothelial cell damage) and restoration of intrahepatic tissue pO2 during reperfusion. Hepatocellular damage was tested by plasma concentrations of aspartate aminotransferase (AST), alanine aminotransferase, and lactate dehydrogenase (LDH). RESULTS: Hyaluronic acid uptake after 6 hours of reperfusion, compared to preischemic uptake, was unaltered in the control group, but was significantly reduced in both resection groups. However, more HA was taken up after INT occlusion, compared to CNT (60.4% +/- 5.6% and 39.5% +/- 3.7%, respectively; ANOVA: p = 0.001). Intrahepatic tissue pO2 distribution after 6 hours of reperfusion more closely returned to preischemic configuration in the INT group than in the CNT group, indicating reduced microcirculatory disturbances after INT occlusion. Release of AST and LDH after 6 hours of reperfusion was significantly increased in both CNT and INT groups. Lower AST levels, however, were found after INT occlusion than after CNT occlusion (267.0 +/- 74.7 U/l and 603.3 +/- 132.4 U/l, respectively; p = 0.06). CONCLUSIONS: Intermittent hepatic vascular inflow occlusion during prolonged liver ischemia in pigs resulted in less microcirculatory and hepatocellular injury, compared to continuous occlusion. Intermittent clamping is preferable when prolonged periods of vascular inflow occlusion are applied during liver resections.     

Two-Day Fasting Prior to Intestinal Ischemia-Reperfusion Injury on Bacterial Translocation in Rats

ABSTRACT

Purpose: The aim of this study is to verify the effect of two-day fasting prior to intestinal ischemia-reperfusion (I/R) injury on bacterial translocation (BT). Materials and Methods: Mail Sprague–Dawley rats were divided into four groups: group 1, control rats that underwent sham operation only; group 2, rats fasted for two days prior to sham operation; group 3, rats that underwent occlusion of mesenteric vessels for 30 min followed by reperfusion for 4 hr; and group 4, rats fasted for two days prior to the same intestinal I/R injury as in group 3. In all groups, E. coli labeled with ^99mTc were inoculated into the terminal ileum. Two hr after inoculation of E. coli, the rats were killed. A segment of ileum was obtained for histological examination and samples of mesenteric lymph nodes (MLNs), liver, lung, blood, and spleen were obtained for radioactivity determination. Results: There were no significant differences in the intestinal mucosa and radioactivity of all samples between groups 1 and 2. Group 3 showed significantly shorter mucosa and villi, and higher radioactivity of samples, except for MLNs, compared to group 1. Group 4 showed similar mucosa and villi, but significantly higher radioactivity of samples, except for MLNs, compared to group 3. Conclusion: Two-day fasting without I/R injury does not cause mucosal change and BT, but in cases following intestinal I/R injury, two-day fasting increases the susceptibility of BT to systemic organs in rats.     

表皮生长因子对重症胰腺炎肠外营养大鼠肠道细菌易位的影响

探讨表皮生长因子（ＥＧＦ）对重症胰腺炎（ＳＡＰ）全肠外营养（ＴＰＮ）支持大鼠肠道细菌易位的影响。方法：４８只ＳＤ大鼠随机分为ＳＡＰ组、ＳＡＰ＋ＴＰＮ组及ＳＡＰ＋ＴＰＮ＋ＥＧＦ组。分别测定肠系膜淋巴结、肝脏及脾脏细菌易位率,利用图像分析仪对小肠粘膜进行检测,并测定回肠粘膜厌氧菌与需氧菌的比率。结果：ＳＡＰ＋ＴＰＮ＋ＥＧＦ组肠系膜淋巴结、肝脏及脾脏细菌易位率明显降低,小肠粘膜绒毛面积、高度、隐窝深度增加,回肠厌氧菌与需氧菌的比率显著提高。结论：ＥＧＦ具有保护重症胰腺炎全肠外营养大鼠肠粘膜机械屏障、生物屏障和降低肠道细菌易位率的作用。     

Bacterial translocation in experimental uremia

The aim of this study was to investigate whether or not experimental uremia would induce bacterial translocation. Forty male Wistar rats were randomized into two groups: uremic (n=20) and control (n=20). Under anesthesia, the upper and lower left renal poles and the marginal lateral parenchyma were excised in uremic group. Seven days later, in a second operation the whole right kidney was removed. In control animals, two sham operations with the same interval were performed. After 60 days from the first operation, the liver, spleen and the mesenteric lymph nodes (MLN) were excised and cultured. Blood samples were sent for biochemical analysis (BUN, creatinine, sodium and potassium) and cultured. Specimens of the jejunum (1 cm below the Treitz angle) and ileum (1 cm above the ileocecal valve) were collected and sent for histological examination and scored for the degree of inflammation of the mucosa using a classification proposed by Chiu et al. in 1970. Uremic rats presented higher BUN, creatinine and potassium than controls. Bacterial translocation was more frequent in uremic than in control animals (8/20 (40%) vs. 1/20 (5%); p=0.02). Translocation in uremic rats was observed mainly at the MLN (all eight cases). Both at the jejunum (uremic=3 [0–5] vs. control=2 [0–4]; p=0.04) and the ileum (uremic=2 [0–5] vs. control=0 [0–3]; p=0.01), inflammation score was higher in uremic rats than in controls. The intestinal mucosa barrier is impaired and bacterial translocation occurs in experimental uremia.     

Hyperbaric oxygen prevents bacterial translocation in thermally injured rats.

This study was designed to evaluate the effects of hyperbaric oxygen (HBO2) on intestinal microflora and bacterial translocation (BT) caused by experimentally induced thermal injury in rats. Rats were separated into four groups, namely, HBO2 group, thermal injury (TI) group, TI + HBO2 group, and control group. All groups were further separated into short-term (2 days) and long-term (7 days) treatment or injury groups. Control group was neither exposed to thermal injury nor was given any treatment. Thirty percent second-degree thermal burn was induced on the dorsal body part of the rats in TI groups. In the HBO2 groups, rats received HBO2 treatment either without TI or following TI induction, for 2 and 7 days, respectively. Sampling from tissues and portal vein was performed on day 3 in the short-term groups and on day 8 in the long-term groups. Samples were cultured for identification of bacteria and colony counts. HBO2 treatment significantly reduced the colony counts of endogenous microflora in distal ileum of healthy rats (p < .05), while TI significantly increased the colony counts of endogenous microflora in distal ileum in short and long-term TI groups (p < .05). Presence of bacterial translocation was proven by bacterial isolation in mesenteric lymph nodes, liver, spleen and blood. Both short- and long-term HBO2 treatment following TI significantly reduced the colony counts of intestinal microflora (p < .05) and prevented bacterial translocation almost completely. It is concluded that thermal injury causes both bacterial overgrowth within intestinal lumen and bacterial translocation across the intestinal wall. HBO2 administration prevents both bacterial overgrowth and translocation.     

天然蒙脱石防治烧伤后肠道细菌移位的实验研究

目的　探讨天然蒙脱石对烧伤大鼠肠道细菌移位的防治作用。　方法　SD大鼠54只,分为正常对照组6只、烧伤对照组与烧伤治疗组各24只。后两组大鼠预先喂服转染了质粒pUC19的示踪菌JM109,证实质粒已定植于其肠道后,制成30%TBSAⅢ度烫伤(以下称烧伤)模型。烧伤治疗组大鼠伤后立即喂服天然蒙脱石0. 6g d-1 kg-1,烧伤对照组大鼠不喂服药物。观察正常对照组大鼠以及烧伤对照组、烧伤治疗组大鼠伤后12h和1、3、5d血液、肠系膜淋巴结细菌移位情况,并行酶切鉴定;检测大鼠肠组织丙二醛(MDA)及超氧化物歧化酶(SOD)的含量;用病理学方法观察整段小肠的损伤情况,测量空肠黏膜绒毛高度并计算基底膜细胞核分裂相。　结果　血液细菌培养:伤后1、5d,烧伤对照组阳性鼠数多于正常对照组,烧伤治疗组阳性鼠数少于烧伤对照组(P<0 05).肠系膜淋巴结细菌定量:烧伤治疗组伤后1、5d为(38±16)、(68±20)集落形成单位(CFU) /g;烧伤对照组伤后1、5d为( 228±67 )、( 183±29 )CFU/g,明显高于前者(P<0. 01 ).MDA、SOD含量:烧伤治疗组与烧伤对照组伤后各时相点比较,差异有统计学意义(P<0. 05).烧伤治疗组大鼠伤后各时相点空肠绒毛高度及基底膜细胞核分裂相明显高于或多于烧伤对照组(P<0. 05或0. 01)。　结论　天然蒙脱石对严重烧伤大鼠肠     

不同入肝血流阻断法行肝硬化大鼠肝切除的比较

目的：比较不同入肝血流阻断法行肝硬化大鼠肝切除的手术安全性及对肝脏、小肠损伤的影响。 方法：大鼠采用CCl4加乙醇复合法诱导肝硬化模型后行Higgins法70%肝切除。根据术中肝血流阻断法的不同分为A组（Pringle法）;B组（半肝血流阻断法）;C组（保留半肝动脉血流阻断法）;D组（门静脉转流保留半肝动脉血流阻断法）,阻断时间均为30 min。比较各组手术成功率,肝切除24 h后动物存活率及肝细胞及小肠病理改变。 结果：A、B、C、D组手术成功率各分别为90.9%（10/11）、76.9%（10/13）、80.3%（10/12）、76.9%（10/13）,组间差异无统计学意义（P>0.05）;肝切除术后24 h存活率分别为3/10（30%）、10/10（100%）、9/10（90%）、10/10（100%）,B、C、D组大鼠存活率均明显高于A组（均P<0.05）。病理学结果显示,A组肝组织、小肠黏膜明显损伤,除C组小肠黏膜损伤与A组类似外,其他各组肝组织损伤均较A组轻微,且小肠黏膜基本无损伤。 结论：在肝硬化大鼠肝切除中,采用半肝血流阻断法、保留半肝动脉血流阻断法、门静脉转流保留半肝动脉血流阻断法的手术安全性及肝损伤程度均优于Pringle法。

     

不同营养方式对肠道缺血再灌注大鼠肠屏障功能的影响

目的探讨不同营养物质及支持途径对肠道缺血再灌注大鼠肠屏障功能和细菌易位的影响。方法60只雄性SD大鼠建立肠道缺血再灌注模型,随机分成普通肠外营养组(PN),富含谷氨酰胺的肠外营养组(G-PN),普通肠内营养组(EN)及免疫增强型肠内营养组(IEN)。从术后第1天起连续营养支持7d,各组等氮、等热卡。观察肠道形态学、肠道黏膜通透性、肠道细菌易位情况和血浆内毒素水平及肠道免疫功能检测。结果PN组肠黏膜明显萎缩,其绒毛高度、黏膜厚度、隐窝深度及绒毛表面积均显著低于其他各组(P<0.05);其肠黏膜通透性及内毒素值显著高于其他各组(P<0.05),细菌易位率(100%)明显高于其他各组(G-PN组60.0%,EN组33.3%,IEN组20.0%)。PN组CD4 T淋巴细胞和IgA 浆细胞分布显著低于其他各组(P<0.01)。结论EN在维护肠黏膜屏障功能、防止细菌及内毒素易位方面优于PN。免疫增强型EN在维护肠黏膜屏障、改善肠道免疫功能、防止细菌易位方面作用优于普通EN。     

Effects of somatostatin analogues and vitamin C on bacterial translocation in an experimental intestinal obstruction model of rats.

The passage of viable endogenous bacteria and their products across the intact intestinal mucosal barrier, disseminating to the mesenteric lymph nodes, peritoneal cavity, spleen, liver, and circulation, is defined as bacterial translocation. Intestinal obstruction induces bacterial translocation due to mucosal disruption, motility dysfunction, and increased intestinal volume, leading to bacterial overgrowth. In a rat model of intestinal obstruction, the effects of both high-dose vitamin C (350 microg/kg), an antioxidant agent known to have a cytoprotective effect in ischemia-reperfusion injury, and somatostatin (20 microg/kg), a gastrointestinal antisecretory agent, in preventing bacterial translocation were studied. Both intestinal and liver samples from the rats was observed, and it was found that the rate of bacterial translocation was 100% in the control group, and only 43% for the rats who were given intraperitoneal vitamin C and somatostatin. The difference was statistically significant. In conclusion, we are convinced that vitamin C and somatostatin analogues may have protective effects against bacterial translocation in mechanical bowel obstruction.