ObjectiveTo explore the mechanism of liver capillary permeability in rats with severe acute pancreatitis (SAP). MethodsTotally 40 healthy Sprague-Dawley (SD) rats were randomly divided into two groups: sham operation (SO) group and SAP group, SAP group were divided into four subgroups according to sampling time (3 h， 6 h, 12 h， and 24 h). The model was established by injecting 5% sodium taurocholate retrogradely into pancreaticobiliary ducts. The changes of tumor necrosis factor-α (TNF-α), pathohistology, and tissue moisture content were compared among different groups. Liver occludin protein expression was analyzed by immunohistochemistry method, and occludin mRNA was measured by RT-PCR. ResultsThere was no significant pathological changes of liver tissue in the SO group. Typical pathological changes of SAP， such as interstitial edema, vasodilatation, infiltration of inflammatory cells, were found in the SAP group. TNF-α level and tissue moisture content of each phase increased gradually, and the highest level appeared at 24 h within the observing period. The two above indicators at different time point in subgroups were significantly different from each other and higher than those in the SO group (Plt;0.05)． In the SAP group, the expression of occludin and it’s mRNA began to decrease at 3 h to the bottom at 6 h and rebounced significantly at 12 h, 24 h compared with those at 6 h (Plt;0.05), but still lower than those in the SO group (Plt;0.05). ConclusionUpregulation in TNF-α and subsequent downregulation in occludin protein and mRNA maybe bly related to the severe liver capillary permeability in rats with SAP.
Objective To establish a stable and reliable lung injury model caused by severe acute pancreatitis（SAP）in rats， which is helpful to study the acute lung injury （ALI）and acute respiratory distress syndrome （ARDS） induced by SAP.Methods Sixty Sprague-Dawley rats were randomized into ligature group （n=20）， traditional group （n=20），and sham operation group （n=20）. SAP model was established through retrograde injection of 5% taurocholic acid. After injection， the pancreatic duct of rats was ligated in ligature group， but not in traditional group. The lung damage and edema at 24 h after operaton and natural course of rats were observed.Results The ALI model of rats induced by SAP was established successfully in ligature group. The rats died of acute respiratory failure within 48 h in ligature group， the mortality was significantly higher than that in traditional group （100% vs.20%），P＜0.05. Pleural effusion occurred in four rats in ligature group， while no pleural effusion was found in rats in other two groups. The volume of ascites of rats in ligature group was （21.15±5.33） ml， which was more than that in traditional group 〔（7.75±2.66） ml〕，P＜0.05， while no ascites was found in rats in sham operation group. The level of serum amylase of rats in ligature group was （2 470.70±399.73） U/L，which was significantly higher than that in traditional group 〔（1 528.40±289.54） U/L〕 and sham operation group 〔（831.10±93.26） U/L〕，P＜0.001. The level of serum albumin of rats in ligature group was （6.90±1.66）g/L， which was significantly lower than that in traditional group 〔（13.10±0.99） g/L〕 and sham operation group 〔（16.20±0.92） g/L〕，P＜0.001.The lung wet-to-dry weight ratio （W/D） of rats in ligature group was 6.50±0.23， which was greater than that in traditional group （4.92±0.18） and sham operation group （4.61±0.16）， P＜0.001. The score of lung histopathologic of rats in ligature group was 29.25±1.07， which was significantly higher than that in traditional group （12.65±1.98） and sham operation group （0），P＜0.001. The score of pancreas histopathologic of rats in ligature group was 15.95±0.15，which was significantly higher than that in traditional group （13.75±0.66） and sham operation group （0.13±0.29），P＜0.001. Under transmission electron microscope， basement membrane of pulmonary capillary of rats in ligation group was destructive， the nuclei was dissolved， endothelial pinocytotic vesicles was functional active， and tight junctions between capillary endothelial cells were blurred and even ruptured. Moreover， tight junctions between alveolar epithelial cells were destructive. Pathological changes of lung ultrastructure of rats in ligation group were more severe than that in traditional group， while no pathological change of lung ultrastructure was observed in rats in sham operation group. Conclusions Injury process and pathogenesis of ALI or ARDS clinically caused by acute gallstone pancreatitis can be reproduced in this animal model， which is suitable to explore the related mechanisms of ALI caused by SAP and provides good animal model for the study of ALI caused by SAP.
The contents of lipid peroxides(LPO)and vitamin E(V.E)and some functional index and histologic changes in the lungs from the the rabbit models of acute cholangitis of severe type(ACST)were measured dynamically.The results revealed that the V.E content decreased strikingly from 6 hours and the LPO level increased progressivelg from 12 hours in the lungs.Simultanuosly,the congestion and neutrophil infiltreation in the lung mesenchyme,and the endothelial cell damage and thrombosis in the lung blood capillaries had been observed.These suggest that acute lung injury induced by ACST is referable to the lipid peroxidation damage to the lung blood capillaries which is due to increased LPO and decreased antioxidants including V.E.
The authors observed the progressive changes of the platelet activity in 25 cases of acute cholangitis severe type(ASCT)within 2 weeks of pre-and-post-operation.The results revealed that there are signficant changes of the platelet activity in ASCT.The levels of the platelet activity were proportional to the severity of disease and degree of biliary duct obstruction.Persistency of abnormality of platelet activity may predict the worse of disease and bad prognosis.The results are useful to understand the complex changes of pathophysiology in ACST,to the mechanism of multiple organic failure.
Objective To investgate the expression of p38 mitogen-activated protein kinase （p38MAPK） in lung tissue of rats with severe acute pancreatitis （SAP）， and to explore the relationship between p38MAPK and pulmonary capillary barrier injury. Methods Forty male and healthy Sprague-Dawley （SD） rats were randomly （random number method） divided into sham operation （SO） group and SAP group， then rats of SAP group were sub-divided into 3， 6， 12， and 24 h group， each group enrolled 8 rats， respectively. SAP model rats were established by injecting 5% sodium taurocholate solution retrograde into the biliopancreatic duct. ELISA method was used to test the serum tumor necrosis factor-α （TNF-α） and interleukin-1β （IL-1β）， and pathological changes in lung and pancreas tissues were observed by HE staining. Immunohischemistry method was used to detect phosphorylated p38 （p-p38） protein and aquaporin 1 （AQP1） protein of lung tissues. The expression level of AQP1 mRNA was measured by quantitative real-time PCR. Results Hyperemia， edema， and inflammatory cell infiltration were observed in lung tissues， abundance of necrosis， part gland structure fuzzy or even disappear were observed in pancreas tissues of all 4 time point groups. Compared with SO group， levels of serum TNF-α and IL-1β were significantly higher in 4 time point groups （P＜0.05）. Lower expression level of p-p38 protein was detected in lung tissues of SO group， while in the early stage of SAP （SAP 3 h group）， the expression level of p-p38 protein significantly increased， which peaked in 6 h group and was still higher than SO group in 24 h group （P＜0.05）. Compared with SO group， the expression levels of AQP1 mRNA and protein were significantly lower in all 4 time point groups （P＜0.05）， which had negative correlation with the levels of serum TNF-α，IL-1β， and the expression level of p-p38 protein （r=-0.87， P＜0.05；r=-0.88， P＜0.05；r=-0.78， P＜0.05）. Conclusion The decrease of AQP1 protein in lung tissue is one of the vital causes for pulmonary capillary barrier injury in SAP， which probably works by the activation of p38MAPK and the excessive release of inflammatory cytokines.
ObjectiveTo study the expression of zonula occluden-1 (ZO-1) in ileum tissues and the possible mechanism of intestinal mucosal barrier injury in rats with severe acute pancreatitis (SAP). MethodsFifty SD male rats were randomly divided into sham operation group and SAP group, then SAP group was divided into four subgroups with 10 rats in each subgroup according to the sampling time of 3, 6, 12, and 24 h. The SAP model was made by injecting 5% bovine sodium deoxycholate into biliarypancreatic duct with Aho’s method. The rats were killed at 3, 6, 12, and 24 h after making model. The rats in the sham operation group were killed directly. Tumor necrosis factor-α (TNF-α), diamine oxidase (DAO), and histological changes in pancreatic and intestinal pathologies were observed. At the same time, the ZO-1 protein and mRNA expressions of ileum tissues were detected by immunohistochemistry and RT-PCR, respectively. ResultsCompared with the sham operation group 〔TNF-α: (10.83±0.96) ng/L; DAO: (354.79±3.67) U/L; ZO-1 protein: (10.40±0.45) score; ZO-1 mRNA: 0.878±0.014 8〕, the levels of TNF-α at different time 〔3 h: (125.30±0.94) ng/L; 6 h: (181.89±4.93) ng/L; 12 h: (230.58±1.28) ng/L; 24 h: (198.89±4.83) ng/L〕 were significantly higher (Plt;0.05), the activities of DAO 〔3 h: (235.77±0.67) U/L; 6 h: (117.22±5.58) U/L; 12 h: (106.69±1.39) U/L; 24 h: (91.18±1.09) U/L〕 were significantly lower (Plt;0.05), ZO-1 protein 〔3 h: (8.70±0.22) score; 6 h: (3.73±0.19) score; 12 h: (3.92±0.22) score; 24 h: (4.29±0.30) score〕 and mRNA (3 h: 0.806±0.020 7; 6 h: 0.370±0.015 8; 12 h: 0.502±0.019 2; 24 h: 0.562±0.030 3) expressions of the ileum tissues were significantly lower (Plt;0.05) in the SAP group; Meanwhile, the necrosis of ileum mucous membrane chorioepithelium, angiorrhexis and hemorrhage, and inflammatory cell infiltration in the pancreatic and ileum tissues were also observed. ConclusionThe decrease of expression of ZO-1 in ileum tissues is one of the vital causes for mucosal barrier injury in SAP, probably through acts the excessive release of inflammatory cytokines TNF-α and the decrease of DAO activity.
Objective To investigate the effect of the duct-to-mucosa anastomosis in invaginating end-to-side pancreaticojejunostomy. Methods A retrospective review was conducted for 200 patients treated with pancreaticoduod-enectomy （PD） between August 2005 and December 2012. Reconstruction of digestive tract in PD was done according to the method described by Child. The duct-to-mucosa anastomosis was applied in the invaginating end-to-side pancrea-ticojejunostomy. The outline of the anastomosis structures was as follows：anastomosis of pancreatic duct and jejunal mucosa， anastomosis of pancreatic and jejunal resection margin， and anastomosis of pancreas and jejunal seromuscular layer. A cilicone tube was put into the pancreatic duct and lead to the jejunum. The anastomotic stoma was covered with part of the omentum majus, and put a drainage tube under the anastomotic stoma. Results The operation went smoothly，and no deaths occurred during perioperative period. The surgical time was 280-420 min， the average time was （298±77） min. The pancreatic fistula were observed in 22 patients （11%）， including 17 patients in Grade A， 2 patients in Grade B， and 3 patients in Grade C. The other complications were observed in 19 patients， including 16 patients with addominal infection， 1 patient with bleeding from splenic vein， 1 patient with bleeding from ruptured of pseudoaneurysm at biliary intestinal anastomosis， 1 patient with abdominal abscess. Three patients with pancreatic fistula in Grade C were cured by reoperation, and the other patients with pancreatic fistula were cured by expectant treatment. Conclusions The duct-to-mucosa anastomosis in invaginating end-to-side pancreaticojejunostomy is a simple and safe procedure that has the advantage in reducing the incidence of the pancreatic fistula. Using omentum to cover the anastomotic could localize the diffusion of panreactic fistula， and reduce the incidence of serious complications caused by pancreatic fistula.