Pancreas recovery following cerulein-induced pancreatitis is impaired in plasminogen-deficient mice

BACKGROUND & AIMS: The plasminogen (plg) system participates in tissue repair in several organs, but its role in pancreas repair remains poorly characterized. To understand better the role of plg in pancreas recovery following injury, we examined the course of cerulein-induced pancreatitis in plg-deficient and -sufficient mice. METHODS: Pancreatitis was induced by cerulein administration (50 microg/kg, 7 intraperitoneal injections). Mice were killed either at the acute phase (7 hours after the first cerulein injection) or during recovery (at 2, 4, and 7 days). In pancreatic sections, we examined pancreatic morphology, trypsin activation, inflammatory cell infiltration, acinar cell death, cell proliferation, extracellular matrix deposition, activation of stellate cells (PSCs), and components of the plg and metalloproteinase systems. RESULTS: In plg-sufficient mice, pancreatic plg levels and plasmin activity increased during the acute phase and remained elevated during recovery. Pancreatitis resolved in plg-sufficient mice within 7 days. Pancreas recovery involved reorganization of the parenchyma structure, removal of necrotic debris, cell proliferation, transient activation of PSCs, and moderate deposition of extracellular matrix proteins. Acute pancreatitis (7 hours) was indistinguishable between plg-deficient and -sufficient mice. In contrast, pancreas recovery was impaired in plg-deficient mice. Plg deficiency led to disorganized parenchyma, extensive acinar cell loss, poor removal of necrotic debris, reduced cell proliferation, and fibrosis. Fibrosis was characterized by deposition of collagens and fibronectin, persistent activation of PSCs, and up-regulation of pancreatic transforming growth factor beta1. CONCLUSIONS: Plg/plasmin deficiency leads to features similar to those found in chronic pancreatitis such as parenchymal atrophy and fibrosis.     

JAM-C单抗对小鼠急性坏死性胰腺炎的抑制作用

目的:观察JAM-C单克隆抗体对小鼠急性坏死性胰腺炎(ANP)模型胰腺和全身炎症的抑制作用.方法:采用雨蛙素和脂多糖联合腹腔注射的方法建立小鼠重症急性胰腺炎模型.生理盐水对照组(NS组):小鼠给予腹腔注射无菌生理盐水(10 mL/kg),共注射6次,间隔1 h;ANP模型组(ANP组):小鼠给予腹腔注射雨蛙素(50μg...     

p38 MAPK inhibition alleviates experimental acute pancreatitis in mice

BACKGROUND: The mitogen-activated protein kinases (MAPKs) signaling pathway is involved in inflammatory process. However,the mechanism is not clear. The present study was to investigate the role of p38 MAPK in acute pancreatitis in mice.METHODS: Mice were divided into 4 groups: saline control; acute pancreatitis induced with repeated injections of cerulein; control plus p38 MAPK inhibitor SB203580; and acute pancreatitis plus SB203580. The pancreatic histology, pancreatic enzymes, cytokines, myeloperoxidase activity, p38 MAPK and heat shock protein (HSP) 60 and 70 were evaluated.RESULTS: Repeated injections of cerulein resulted in acute pancreatitis in mice, accompanying with the activation of p38 MAPK and overexpression of HSP60 and HSP70 in the pancreatic tissues. Treatment with SB203580 significantly inhibited the activation of p38 MAPK, and furthermore, inhibited the expression of HSP60 and HSP70 in the pancreas, the inflammatory cytokines in the serum, and myeloperoxidase activity in the lung.CONCLUSION: The p38 MAPK signaling pathway is involved in the regulation of inflammatory response and the expression of HSP60 and HSP70 in acute pancreatitis.     

A proinflammatory, antiapoptotic phenotype underlies the susceptibility to acute pancreatitis in cystic fibrosis transmembrane regulator (-/-) mice

BACKGROUND & AIMS: Cystic fibrosis transmembrane regulator (CFTR) gene mutations are associated with pancreatic insufficiency and pancreatitis. Chronic pancreatitis, including cystic fibrosis-related disease, may exist as a continuum between acute and chronic disease and may manifest as recurrent pain. We hypothesized that cftr(m1UNC) (-/-) mice, which have no evidence of chronic pancreatitis, are susceptible to developing acute pancreatitis. METHODS: We used a cerulein hyperstimulation model of acute pancreatitis and measured histological changes, tissue edema, neutrophil infiltration, inflammatory mediators' mRNA expression, apoptosis markers, and pancreatic trypsin and serum lipase activities. Additionally, we quantitated in vivo pancreatic secretion and pancreatic digestive enzymes. RESULTS: Multiple proinflammatory cytokine genes were constitutively overexpressed in cftr (-/-) pancreas compared with wild-type mice. During acute pancreatitis, cftr (-/-) mice developed more severe acute pancreatitis than wild-type, as indicated by greater pancreatic edema, neutrophil infiltration, mRNA expression of multiple inflammatory mediators, and less apoptotic cell death. In contrast to wild-type mice, cftr (-/-) mice had blunted increases in pancreatic trypsin and serum lipase activities, but similar percentages of pancreatic trypsinogen activation. Finally, cftr (-/-) mice had less in vivo pancreatic secretion in response to cholecystokinin octapeptide and reduced pancreatic digestive enzyme protein and mRNA levels, thus suggesting mild pancreatic insufficiency. CONCLUSIONS: A baseline proinflammatory state and an antiapoptotic phenotype may sensitize cftr (-/-) mice to developing more severe acute pancreatitis with an exuberant pancreatic inflammatory response. Cftr (-/-) mice have mild pancreatic insufficiency, which partially explains the blunted increase of pancreatic and serum digestive enzymes during acute pancreatitis. These findings may explain the susceptibility to acute pancreatitis in persons with classic and nonclassic cystic fibrosis.     

Induction of acute pancreatitis by cerulein in human IL-6 gene transgenic mice

Whether acute pancreatitis induced by cerulein was aggravated in human interleukin 6 (IL-6) transgenic mice and whether a specific anti-IL-6 receptor antibody improved pancreatitis were investigated. To induce acute pancreatitis, cerulein (50 microg/kg, seven injections) with or without 1 mg/kg lipopolysaccharides (LPS) was injected intraperitoneally every hour. In some mice, a monoclonal anti-IL-6 receptor antibody was administered before the first cerulein injection. The animals were killed 1 hour after the last injection. The pancreatic wet weight induced by cerulein alone was significantly higher in IL-6 transgenic mice compared with wild-type mice, but pretreatment with a specific anti-IL-6 receptor antibody did not reduce interstitial edema. When cerulein was administered with LPS, the pancreatic wet weight increased much more than when pancreatitis was induced by cerulein alone in both genotypes, and pretreatment with the anti-IL-6 receptor antibody decreased the pancreatic edema only in human-IL-6 transgenic mice. These results suggest that anticytokine antibodies may be effective in improving acute pancreatitis.     

Adiponectin deficiency enhanced the severity of cerulein-induced chronic pancreatitis in mice

Background

Adiponectin is recognized as an antiinflammatory and antifibrotic protein derived from adipocytes, and low serum adiponectin levels are present in obesity. Recent studies have highlighted the relationship between obesity and pancreatic diseases. However, the role of adiponectin in chronic pancreatitis remains uncertain. The aim of this study was to determine the effects of adiponectin in chronic pancreatitis.

Methods

We investigated the effects of adiponectin in experimental chronic pancreatitis by using adiponectin-knockout (APN-KO) mice. Chronic pancreatitis was induced by repeated hourly (6 times) intraperitoneal injections of 50 µg/kg cerulein three times per week for 4 weeks in wild-type (WT) and APN-KO mice. We evaluated the severity of chronic pancreatitis biochemically and morphologically.

Results

In cerulein-treated mice, macroscopically and histologically, severe pancreatic damage was observed in APN-KO mice compared with findings in WT mice. The histological scores for chronic pancreatitis, including glandular atrophy, pseudotubular complex, fibrosis, and total scores, were significantly higher in APN-KO mice than in WT mice. Activated pancreatic stellate cells and F4/80-positive pancreatic macrophages accumulated in the pancreas of APN-KO mice but not in WT mice. Overexpression of the mRNAs of transforming growth factor-β1, CD68, and monocyte chemoattractant protein-1 was noted in APN-KO mice but not in WT mice. The gene expression level of collagen1 (α1) tended to be higher in APN-KO mice than in WT mice, albeit insignificantly.

Conclusions

Adiponectin deficiency enhanced the severity of cerulein-induced chronic pancreatitis in mice. Hypoadiponectinemia could enhance the severity of chronic pancreatitis.     

Evidence for a role of free radicals by synthesized scavenger, 2-octadecylascorbic acid,in cerulein-induced mouse acute pancreatitis

To define the role of free radicals and of lipid peroxide involvement during the progress of cerulein-induced acute pancreatitis in mice, we evaluated the effect of a novel free radical scavenger, 2-octadecylascorbic acid (CV-3611), on pancreatic edema formation, and the levels of serum enzymes (amylase, lipase) and of lipid peroxide in pancreatic tissue. Mice were divided into three groups: control group, intraperitoneal injection of saline only; pancreatitis group, cerulein 50 g/kg injected intraperitoneally six times at 1-hr intervals; treatment group, CV-3611 10 mg/kg subcutaneously just after intraperitoneal cerulein injection. After the cerulein injection, the degree of pancreatic edema formation, serum amylase and lipase levels, and the amount of lipid peroxide in pancreatic tissue increased significantly during the observation period of 12 hr. Treatment with CV-3611 resulted in significant reduction in pancreatic edema formation at 3.5 hr (P<0.05) and 9 hr (P<0.05), serum amylase and lipase levels at 3.5 hr (P<0.05) and 12 hr (P<0.05), and lipid peroxide levels at 3.5 hr (P<0.05), 6 hr (P<0.05) and 12 hr (P<0.05). These results indicate that a novel free radical scavenger, CV-3611, has a strong therapeutic effect during the development of acute pancreatitis and suggest that oxygenderived free radicals play an important role in the pathogenesis of acute pancreatitis.     

Cholinergic Mediation of Alcohol‐Induced Experimental Pancreatitis

Objectives: The mechanisms initiating pancreatitis in patients with chronic alcohol abuse are poorly understood. Although alcohol feeding has been previously suggested to alter cholinergic pathways, the effects of these cholinergic alterations in promoting pancreatitis have not been characterized. For this study, we determined the role of the cholinergic system in ethanol‐induced sensitizing effects on cerulein pancreatitis. Methods: Rats were pair‐fed control and ethanol‐containing Lieber‐DeCarli diets for 6 weeks followed by parenteral administration of 4 hourly intraperitoneal injections of the cholecystokinin analog, cerulein at 0.5 μg/kg. This dose of cerulein was selected because it caused pancreatic injury in ethanol‐fed but not in control‐fed rats. Pancreatitis was preceded by treatment with the muscarinic receptor antagonist atropine or by bilateral subdiaphragmatic vagotomy. Measurement of pancreatic pathology included serum lipase activity, pancreatic trypsin, and caspase‐3 activities, and markers of pancreatic necrosis, apoptosis, and autophagy. In addition, we measured the effects of ethanol feeding on pancreatic acetylcholinesterase activity and pancreatic levels of the muscarinic acetylcholine receptors m1 and m3. Finally, we examined the synergistic effects of ethanol and carbachol on inducing acinar cell damage. Results: We found that atropine blocked almost completely pancreatic pathology caused by cerulein administration in ethanol‐fed rats, while vagotomy was less effective. Ethanol feeding did not alter expression levels of cholinergic muscarinic receptors in the pancreas but significantly decreased pancreatic acetylcholinesterase activity, suggesting that acetylcholine levels and cholinergic input within the pancreas can be higher in ethanol‐fed rats. We further found that ethanol treatment of pancreatic acinar cells augmented pancreatic injury responses caused by the cholinergic agonist, carbachol. Conclusion: These results demonstrate key roles for the cholinergic system in the mechanisms of alcoholic pancreatitis.     

Gallbladder Emptying to Endogenous and Exogenous Stimulation in Chronic Pancreatitis Patients

Objectives : The present study was designed to analyze the underlying mechanism of gallbladder motor disturbance in chronic pancreatitis patients. Methods : Gallbladder emptying to endogenous (oral test meal, Daiyan 13 g) and exogenous stimulation (iv cerulein, 30 ng/kg for 5 min) was examined by real-time ultrasonography in 12 patients with chronic pancreatitis and 10 normal subjects (controls). Plasma cholecystokinin levels during the endogenous stimulation were measured by bioassay. Results : In chronic pancreatitis patients compared with controls, the fasting allbladder volume was significantly increased (29.5 ± 2.2 vs. 21.5 ± 2.8 ml), whereas the gallbladder emptying (percent change of the basal volume) to oral test meal was significantly decreased. Neither cholecystokinin secretion induced by the test meal, nor the gallbladder emptying response to intravenous cerulein, differed signiHcantly between the two groups. However, when chronic pancreatitis patients were divided according to pathogenesis, it became clear that gallbladder emptying to intravenous cerulein was significantly greater in patients with alcoholic chronic pancreatitis than in patients with idiopathic pancreatitis. Conclusions: Gallbladder emptying during the intestinal phase Is generally reduced in patients with chronic pancreatitis, but gallbladder responsiveness to exogenous stimulation might be heterogeneous according to the pathogenesis.     

Therapeutic effect of DA-9601 on chronic reflux gastritis induced by sodium taurocholate in rats

AIM: To investigate the therapeutic effects of DA-9601 on sodium taurocholate (TCA)-induced chronic reflux gastritis in SD rats. METHODS: In this study, we have investigated the therapeutic effects of DA-9601 on chronic erosive and atrophic gastritis induced by 6 mo of TCA administration (5 mmol/L in drinking water) in SD rats. RESULTS: Four weeks of DA-9601 administration (0.065%, 0.216% in rat chow), following the withdrawal of TCA treatment, resulted in a significant decrease in total length of erosions in rats in a dose-dependent manner. Furthermore, the indicators of atrophic gastritis, such as reduced mucosal thickness and reduction in the number of parietal cells, were improved by the administration of DA-9601 in a dose-related manner. DA-9601 also attenuated inflammatory cell infiltration and the proliferation of collagenous fiber in the gastric mucosa. The improvement in the reduction of the gastric mucus was observed in the rats receiving a high dose of DA-9601 (0.216%). The therapeutic effect of DA-9601 on experimental chronic erosive gastritis was superior to that of rebamipide (1.08% in rat chow). Biochemical analyses showed increased mucosal prostaglandin E2 and reduced glutathione levels by DA-9601 treatment. CONCLUSION: We suggest that DA-9601 is a promising agent for the treatment of chronic erosive and atrophic gastritis with an etiological factor of bile reflux. Increased mucosal prostaglandin E2 and reduced glutathione by DA-9601 treatment may be therapeutic mechanisms for chronic erosive and atrophic gastritis.     

Effects of stress on the development of chronic pancreatitis.

In this study, the effects of chronic water immersion stress on the pancreas were investigated in four groups of rats (each group, n = 9): stress + cerulein group, stress group, cerulein group, and control group. Stress + cerulein rats were treated with water immersion stress for 5 h and two intraperitoneal injections of 20 micrograms/kg body wt of cerulein once a week for 16 weeks. In the macroscopic findings of the pancreas, all rats in the stress+cerulein group exhibited moderate or distinctive congestion of blood vessels, gland atrophy, and fatty changes, while some of them showed bleeding. Microscopically, they all exhibited moderate or severe fibrosis, inflammatory cell infiltration, fatty changes, destruction of lobular architecture, and hemosiderin deposits, while some of them also showed bleeding. The stress group without treatment with cerulein injections showed slight fibrosis, hemosiderin deposits, and bleeding. The cerulein group without stress treatment showed fatty changes, but no inflammatory cell infiltration or fibrosis. In the stress + cerulein group only, the contents of digestive enzymes and protein in the pancreas were approximately 55% lower than those of the control group, whereas those in other groups did not show significant reduction. These findings suggest that stress plays some role in the development of chronic pancreatitis, perhaps by causing circulatory disturbance and blood vessel injury.     

Susceptibility to cerulein-induced pancreatitis in inducible nitric oxide synthase-deficient mice.

Production of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) has been proposed as a pathogenic factor in acute pancreatitis, but its role has still not been fully examined. The present study explored the role of iNOS in cerulein-induced acute pancreatitis using iNOS-deficient mice. Twelve- to 14-week-old male mice (C57B1/6 and iNOS-deficient) were administered cerulein by intraperitoneal (i.p.) injection at hourly intervals for 7 hours and killed 24 hours later after the first dose. Pancreatic wet weight, pancreatic myeloperoxidase (MPO) activity, and levels of plasma nitrite and serum amylase were measured. In another experiment isosorbide dinitrate (an NO donor) was given by oral gavage every 6 hours for 24 hours beginning simultaneously with cerulein injections in iNOS-deficient mice. Cerulein administration dose-dependently increased pancreatic wet weight, myeloperoxidase activity, and levels of nitrite and amylase in C57B1/6 mice. These parameters (except nitrite levels) were significantly intensified in iNOS-deficient mice. At the dose employed, cerulein failed to increase nitrite levels in iNOS-deficient mice. The susceptibility to cerulein toxicity in iNOS-deficient mice was abolished by NO donor treatment. NO release from an iNOS source appears to play a protective role in cerulein-induced pancreatitis. At least in part, NO may prevent neutrophil accumulation after cerulein administration.     

DA-9601 for erosive gastritis： Results of a double-blind placebo-controlled phase III clinical trial

AIM: To determine the efficacy and safety of DA-9601 on erosive gastritis versus cetraxate as a standard drug by gastrointestinal endoscopy. METHODS: Five hundred and twelve patients with erosive gastritis were divided into three groups. The groups received 180 mg or 360 mg of DA-9601, or 600 mg of cetraxate (Neuer) t.i.d. for 2 wk, respectively. Endoscopic observations were performed before and 2 wk after the treatment, and the cure and improvement rates were investigated. RESULTS: Of the 512 intention-to-treat (ITT) population, 457 patients comprised the per protocol (PP) analysis. Endoscopic cure rate was significantly higher in the DA-9601 group than in the cetraxate group in both the PP (56%, 58% vs 36%; DA-9601 180 mg, 360 mg and cetraxate, respectively) and ITT (52%, 51% vs 35%) populations. Two DA-9601 groups (180 and 360 mg) had significantly higher endoscopic improvement rates than the cetraxate group in both the PP (67%, 65% vs 46%) and ITT (63%, 58% vs 45%) populations. The percentage of symptom relief over the 2 wk was found not significantly different between groups. During the study, both DA-9601 and cetraxate produced no treatment-associated adverse events. CONCLUSION: From these results, it appears that DA-9601 has excellent efficacy on erosive gastritis. This study also confirms the safety profile of DA-9601.     

Does stress play a role in the development of severe pancreatitis in rats?

The purpose of this study was to investigate whether stress plays a role, morphologically and enzymatically, in the development of severe pancreatitis in rats. Acute hemorrhagic pancreatitis was induced by two intraperitoneal injections of cerulein (40 micrograms/kg body wt) at intervals of 1 h under water-immersion stress for 5 h, whereas water-immersion stress alone did not induce any morphologic and enzymatic changes in the pancreas. In this model, hemorrhagic pancreatitis developed continuously, and the serum amylase level and activation of zymogen proteases in pancreatic tissue were significantly higher than in cerulein-induced pancreatic tissue 5 h after the first cerulein injection. Furthermore, the effects of cerulein on the serum amylase level and activation of zymogen proteases were dose related. Even 5 micrograms/kg body wt of cerulein, which did not induce any evident edematous change in the pancreas, could activate the zymogen proteases of pancreatic tissue fairly well under water-immersion stress compared with pancreatitis induced by 40 micrograms/kg body wt of cerulein alone. These results indicate that stress accelerates the activation of zymogen proteases induced by cerulein and suggest the possibility that stress may play some role in the development of severe pancreatitis.     

DA-9601 for erosive gastritis:Results of a double-blind placebo-controlled phase Ⅲ clinical trial

AIM: To determine the efficacy and safety of DA-9601 on erosive gastritis versus cetraxate as a standard drug by gastrointestinal endoscopy.METHODS: Five hundred and twelve patients with erosive gastritis were divided into three groups. The groups received 180 mg or 360 mg of DA-9601, or 600 mg of cetraxate (NeuerTM) t.i.d, for 2 wk, respectively. Endoscopic observations were performed before and 2 wk after the treatment, and the cure and improvement rates were investigated.RESULTS: Of the 512 intention-to-treat (ITl) population,457 patients comprised the per protocol (PP) analysis.Endoscopic cure rate was significantly higher in the DA9601 group than in the cetraxate group in both the PP (56%, 58% vs36%; DA-9601 180 mg, 360 mg and cetraxate,respectively) and ITT (52%, 51% vs 35%) populations.Two DA-9601 groups (180 and 360 mg) had significantly higher endoscopic improvement rates than the cetraxate group in both the PP (67%, 65% vs 46%) and ITT (63%,58% vs 45%) populations. The percentage of symptom relief over the 2 wk was found not significantly different between groups. During the study, both DA-9601 and cetraxate produced no treatment-associated adverse events.CONCLUSION: From these results, it appears that DA9601 has excellent efficacy on erosive gastritis. This study also confirms the safety profile of DA-9601.     

Manifestations of experimental acute pancreatitis in young and old rats

Two kinds of experimental pancreatitis were induced in young (4-6 month) and old (25-27 month) female Wistar rats: acute edematous pancreatitis was induced by intraperitoneal administration of a high dose of cerulein (40 micro/kg x 2) and acute hemorrhagic pancreatitis was intraductal injection of 1% deoxycholic acid. After these treatments, the plasma amylase concentration and pancreatic wet weight were determined and the pancreas was examined histologically. In the groups with cerulein induced pancreatitis one of eight old rats died, whereas all five young rats survived. There was no specific finding macroscopically in the liver, kidney, lung or heart of old rats at autopsy after cerulein injection. The plasma amylase concentration and the pancreatic wet weight were significantly increased by administration of cerulein or deoxycholic acid in both young and old rats. There was no significant difference in the plasma amylase concentrations in young and old rats after the induction of acute pancreatitis. The increase in pancreatic wet weight was less in old rats than in young ones after deoxycholic acid treatment, but similar in the two groups after cerulein injection. The extents of histological changes were also similar in young and old rats. Thus, no evidence that aging increases susceptibility to pancreatitis was obtained.     

Macrophage migration inhibitory factor is a critical mediator of severe acute pancreatitis

BACKGROUND & AIMS: Macrophage migration inhibitory factor (MIF), originally described as an inhibitor of the random migration of macrophages, has been shown recently to be involved in the pathogenesis of several inflammatory diseases such as sepsis. The aim of this study was to clarify the role of MIF in acute pancreatitis (AP). METHODS: Hemorrhagic necrotizing pancreatitis and edematous pancreatitis were induced by the injection of taurocholic acid (TCA pancreatitis) and cerulein (cerulein pancreatitis), respectively, on male Wistar rats. MIF levels in ascitic fluids, serum, and the organs were determined. The effects of anti-MIF antibody were examined on the prognosis of rats with TCA pancreatitis and of female CD-1 mice with choline-deficient, ethionine-supplemented, diet-induced model of severe AP. In addition, serum MIF levels in AP patients and in healthy controls were measured. RESULTS: Serum and ascitic MIF levels in TCA pancreatitis were increased rapidly and decreased gradually thereafter. Ascitic MIF levels were also increased in cerulein pancreatitis, but to a lesser degree. MIF level was increased in the lung in TCA pancreatitis, but not in the pancreas and the liver. Prophylactic (1 hour before and immediately after induction) administration of anti-MIF antibody significantly improved the survival rate of rats with TCA pancreatitis. The survival rate of mice with severe AP was also improved significantly by the antibody treatment. Serum MIF levels were higher in severe AP patients than mild AP patients and healthy controls. CONCLUSIONS: These results suggest a role of MIF in the pathogenesis of severe AP.     

Pathophysiology of chronic pancreatitis induced by dibutyltin dichloride joint ethanol in mice

AIM: To search for a new chronic pancreatitis model in mice suitable for investigating the pathophysiological processes leading to pancreatic fibrosis.METHODS: The mice were randomly divided into 2 groups(n = 50), control group and model group. The mice in model group were given ethanol(10%) in drinking water after injection of dibutyltin dichloride(DBTC)(8 mg/kg BW) in tail vein. The mice in control group were injected with only solvent into tail vein( 60 % ethanol, 20% glycerine and 20% normal saline) and drank common water. At days 1, 7, 14, 28, and 56 after application of DBTC or solvent, 10 mice in one group were killed at each time point respectively. Blood was obtained by inferior vena cava puncture. The activity of amylase, concentration of bilirubin and hyaluronic acid in serum were assayed. The pancreas was taken to observe the pancreatic morphology by HE staining, and to characterize the pancreatic fibrosis by Masson staining. The expression of F4/80, CD3 and fibronectin(FN) were assayed by immuno-histochemistry or Immunofluorescence technique. Collagen typeⅠ(COL1A1) in pancreas were detected by Western blot. The expression of matrix metalloproteinase-1(MMP-1) and tissue inhibitor of metalloproteinases-1(TIMP-1) m RNA in the pancreas was assessed by real time PCR.RESULTS: DBTC induced an acute edematous pancreatitis within 1 d. The dilated acini, scattered acinar cell necrosis, and inflammatory cells were found at day 7. Extensive infiltration with inflammatory cells following deposition of connective tissue was observed at day 14. At day 28, level of pancreatic fibrosis was aggravated. The pancreatic tissue was replaced by an extended interstitial fibrosis at the end of 2 mo. There was significant difference in the level of amylase, bilirubin and hyaluronic acid in serum between control group and model group(P 0.05). The level of COL1A1 and FN in pancreas increased. The expression of MMP-1 m RNA in pancreas decreased, but TIMP-1 m RNA increased at model group.CONCLUSION: DBTC joint Ethanol drinking can induce chronic pancreatitis in accordance with the pathophysiological modification of human. DBTC joint Ethanol-induced pancreatitis in mice is an effective and handy experimental method. The model is suitable to study the mechanism of pancreatic fibrosis in chronic pancreatitis.