Acute Necrotizing Pancreatitis In Rats Research Articles

Colonic mucin-2 attenuates acute necrotizing pancreatitis in rats by modulating intestinal homeostasis.

Mucin-2 (MUC2) secreted by goblet cells participates in the intestinal barrier, but its mechanism in acute necrotizing pancreatitis (ANP) remains unclear. In acute pancreatitis (AP) patients, the functions of goblet cells (MUC2, FCGBP, CLCA1, and TFF3) decreased, and MUC2 was negatively correlated with AP severity. ANP rats treated with pilocarpine (PILO) (PILO+ANP rats) to deplete MUC2 showed more serious pancreatic and colonic injuries, goblet cell dysfunction, gut dysbiosis, and bacterial translocation than those of ANP rats. GC-MS analysis of feces showed that PILO+ANP rats had lower levels of butyric acid, isobutyric acid, isovaleric acid, and hexanoic acid than those of ANP rats. The expression of MUC2 was associated with colonic injury and gut dysbiosis. All these phenomena could be relieved, and goblet cell functions were also partially reversed by MUC2 supplementation in ANP rats. TNF-α-treated colonoids had exacerbated goblet cell dysfunction. MUC2 expression was negatively correlated with the levels of pro-inflammatory cytokines (IL-1β and IL-6) (p < .05) and positively related to the expression of tight junction proteins (Claudin 1, Occludin, and ZO1) (p < .05). Downregulating MUC2 by siRNA increased the levels of the pro-inflammatory cytokines in colonoids. MUC2 might maintain intestinal homeostasis to alleviate ANP.

Experimental study on the mechanism of glycogen synthase kinase-3β inhibitor on acute kidney injury of acute necrotizing pancreatitis in rats

To explore the protective mechanism of glycogen synthase kinase-3β (GSK-3β) inhibitor TDZD-8 on acute necrotizing pancreatitis (ANP) associated kidney injury in rats. SPF male Wistar rats were randomly divided into four groups (n = 20): sham operation group (Sham group), ANP model group, TDZD-8 intervention group and TDZD-8 control group. The rat ANP model was prepared by retrograde injection of 5% sodium taurocholate into the bile duct; the same volume of normal saline was injected into the pancreatic duct of the Sham group. The TDZD-8 intervention group and the TDZD-8 control group were injected with GSK-3β inhibitor TDZD-8 (1 mL/kg) via the femoral vein 30 minutes before the model or sham operation; the ANP model group and the Sham group were injected equal volume of 10% dimethyl sulfoxide (DMSO). Rats in each group were sacrificed at 12 hours after operation to measure the serum amylase (AMY), blood lipase (LIPA), serum creatinine (SCr) and blood urea nitrogen (BUN) levels and to observe the pathological changes of pancreatic tissues and kidney tissues. Ultrastructural change of renal cells was analyzed by transmission electron microscopy. Serum interleukin-1β (IL-1β) and interleukin-6 (IL-6) levels were evaluated by enzyme linked immunosorbent assay (ELISA). The activation of nuclear factor-ΚBp65 (NF-ΚBp65) was evaluated by immunohistochemistry assay. The protein expressions of GSK-3β, phospho-GSK-3β (Ser 9), tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), intercellular adhesion molecule-1 (ICAM-1) and interleukin-10 (IL-10) in the kidney were determined by Western Blot. Compared with the Sham group, the serum and inflammatory factors levels of the ANP model group were significantly increased, the pathological damage of the pancreas and kidney tissues were severe, the histopathological score was significantly increased, the expression of NF-ΚBp65 was enhanced in the nucleus of the kidney tissue, and the expressions of GSK-3β, TNF-α, ICAM-1 and iNOS were significantly enhanced, and the expressions of p-GSK-3β(Ser 9) and IL-10 were significantly attenuated. Compared with the ANP model group, TDZD-8 pretreatment significantly reduced serum and inflammatory factor levels in the ANP model group [AMY (kU/L): 5.60±0.30 vs. 10.07±0.34, LIPA (U/L): 1 111.0±110.8 vs. 2 375.0±51.1, SCr (μmol/L): 47.38±1.48 vs. 72.50±2.43, BUN (mmol/L): 17.6±1.0 vs. 26.0±1.0, IL-1β (ng/L): 195.90±5.50 vs. 332.40±38.29, IL-6 (ng/L): 246.10±26.74 vs. 385.30±32.19, all P < 0.01]; pathological damage of pancreas and kidney tissue (histopathological score: 7.1±0.4 vs. 12.1±0.3, 301.2±7.5 vs. 433.5±13.8, both P < 0.01) and ultrastructural damage of renal cells were alleviated; the expression of NF-ΚBp65 in the nucleus was significantly decreased; the expression of p-GSK-3β (Ser 9) was significantly increased, and blocking GSK-3β activity could inhibit the expressions of TNF-α, ICAM-1, iNOS and increase the expression of IL-10, while the expression of GSK-3β in renal tissues was not statistically significant. There were no significant differences between the TDZD-8 control group and the Sham group. Blockade of GSK-3β activity by TDZD-8 exerts the protective effect against kidney injury by inhibiting the inflammation signaling pathway in ANP. It can alleviate histopathological and ultrastructural changes in kidney injury, which protection mechanism is mediated by NF-ΚB and its related inflammatory mediators.

Glycogen synthase kinase-3 beta inhibitors protectagainst the acute lung injuries resulting from acute necrotizing pancreatitis.

Purpose The research is intended for clarification of the efficacy as well as the underlying mechanism of GSK-3β inhibitors on the advancement of acute lung injuries in acute necrotizing pancreatitis (ANP) in rats.Methods Seventy-two rats were randomly divided into 6 groups: (1)ANP-vehicle; (2)ANP-TDZD-8;(3)ANP-SB216763;(4)Sham-vehicle;(5)Sham-TDZD-8;(6)Sham-SB216763; Blood biochemical test, histopathological examination and immunohistochemical analysis of rats pancreas and lung tissues were performed. The protein expression of GSK-3β, phospho-GSK-3β (Ser9), iNOS, ICAM-1, TNF-α, and IL-10 were detected in lung tissues by Western-blot.Results The outcomes revealed that the intervention of GSK-3β inhibitors alleviated the pathological damage of pancreas and lung (P<0.01), reduced serum amylase, lipase, hydrothorax and lung Wet-to-Dry Ratio, attenuated serum concentrations of IL-1β and IL-6 (P<0.01), inhibited the activation of NF-κB, and abated expression of iNOS, ICAM-1 and TNF-α protein, but up-regulated IL-10 expression in lung of ANP rats (P<0.01). The inflammatory response and various indicators in ANP-TDZD-8 groups were lower than those in ANP-SB216763 groups.Conclusions Inhibition of GSK-3β weakens acute lung injury related to ANP via the inhibitory function of NF-κB signaling pathway. Different kinds of GSK-3β inhibitors have different effects to ANP acute lung injury.

Magnesium isoglycyrrhizinate alleviates liver injury in obese rats with acute necrotizing pancreatitis

ObjectiveFor patients with acute necrotizing pancreatitis (ANP), a high body mass index (BMI) increases the likelihood of acute hepatic injury (AHI). In the current study, we explored whether magnesium isoglycyrrhizinate (MgIg) could alleviate ANP-induced liver injury in obese rats. MethodsSprague-Dawley (SD) rats were selected for the present study, and the ANP model was established by retrograde injection of 5% sodium taurocholate into the biliary-pancreatic duct. Thirty-six SD rats were randomly assigned to six groups: the normal (N), standard rat chow (SRC) normal (SN), SRC ANP (S-ANP), high-fat diet (HFD) normal (H–N), HFD ANP (H-ANP), and MgIg pretreatment HFD ANP (H-ANPT) groups. The rats in the H-ANPT group were treated with MgIg (30 mg/kg) intragastrically for 7 days before the ANP model was established. The rats were sacrificed 12 h after ANP was established, and the blood and pancreatic and liver tissues were collected. Differences in the physiology, pathology and cellular and molecular responses of the rats in each group were examined. ResultAnalyses of serum amylase lipase, alanine aminotransferase and aspartate aminotransferase indicated that obesity aggravated ANP-induced hepatic injury and that MgIg improved liver function. The superoxide dismutase, malondialdehyde, M1 macrophage, M2 macrophage, neutrophil, NF-κB, IL-1β and caspase-3 levels in liver tissue showed that MgIg attenuated H-ANP-induced hepatic injury by inhibiting oxidative stress and inflammation. ConclusionObesity aggravated ANP-induced liver injury via oxidative stress and inflammatory reactions. MgIg alleviated oxidative stress and decreased the inflammatory reaction, protecting the liver against the AHI induced by ANP in obese rats.

Underexpression of Receptor for Activated C Kinase 1 (RACK1) in Leukocytes from Patients with Severe Acute Pancreatitis

Receptor for activated C kinase 1 (RACK1) plays an important role in regulating the immune response and cytokine expression. However, little is known about its role in acute pancreatitis (AP). We therefore investigated the role of RACK1 in AP and explored its relationship with interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), both of which are related to AP severity. Two rat models of chemically induced AP with different severities were used: acute edematous pancreatitis (AEP) and acute necrotizing pancreatitis (ANP). The expression levels of IL-6 and TNF-α mRNAs and proteins were significantly increased in leukocytes from AEP and ANP rats, compared with the levels in the control animals, while the expression levels of RACK1 mRNA and protein were significantly decreased in leukocytes from these AP rats. Moreover, the RACK1 levels in leukocytes were significantly lower in ANP rats than those in AEP rats. Consequently, AP patients and healthy volunteers (HVs) were enrolled in this study. Compared with the HVs (n = 5), the expression levels of IL-6 and TNF-α mRNAs and proteins were significantly higher in leukocytes from 15 AP patients, including patients with mild AP (n = 5). By contrast, the expression levels of RACK1 mRNA and protein in leukocytes were significantly lower among patients with severe AP (n = 5) and with moderately severe AP (n = 5), compared with the HVs. The expression levels of RACK1 mRNA were negatively correlated with the IL-6 and TNF-α mRNA levels. Thus, RACK1 may alleviate the severity of AP.

Dysbiosis of Intestinal Microbiota and Decreased Antimicrobial Peptide Level in Paneth Cells during Hypertriglyceridemia-Related Acute Necrotizing Pancreatitis in Rats.

Hypertriglyceridemia (HTG) aggravates the course of acute pancreatitis (AP). Intestinal barrier dysfunction is implicated in the pathogenesis of AP during which dysbiosis of intestinal microbiota contributes to the dysfunction in intestinal barrier. However, few studies focus on the changes in intestine during HTG-related acute necrotizing pancreatitis (ANP). Here, we investigated the changes in intestinal microbiota and Paneth cell antimicrobial peptides (AMPs) in HTG-related ANP (HANP) in rats. Rats fed a high-fat diet to induce HTG and ANP was induced by retrograde injection of 3.5% sodium taurocholate into biliopancreatic duct. Rats were sacrificed at 24 and 48 h, respectively. Pancreatic and ileal injuries were evaluated by histological scores. Intestinal barrier function was assessed by plasma diamine oxidase activity and D-lactate level. Systemic and intestinal inflammation was evaluated by tumor necrosis factor alpha (TNFα), interleukin (IL)-1β, and IL-17A expression. 16S rRNA high throughput sequencing was used to investigate changes in intestinal microbiota diversity and structure. AMPs (α-defensin5 and lysozyme) expression was measured by real-time polymerase chain reaction (PCR) and immunofluorescence. The results showed that compared with those of normal-lipid ANP (NANP) groups, the HANP groups had more severe histopathological injuries in pancreas and distal ileum, aggravated intestinal barrier dysfunction and increased TNFα, IL-1β, and IL-17A expression in plasma and distal ileum. Principal component analysis showed structural segregation between the HANP and NANP group. α-Diversity estimators in the HANP group revealed decreased microbiota diversity compared with that in NANP group. Taxonomic analysis showed dysbiosis of intestinal microbiota structure. In the HANP group, at phyla level, Candidatus_Saccharibacteria and Tenericutes decreased significantly, whereas Actinobacteria increased. At genus level, Allobaculum, Bifidobacterium, and Parasutterella increased significantly, while Alloprevotella, Anaerotruncus, Candidatus_Saccharimonas, Christensenellaceae_R-7_group, Rikenellaceae_RC9_gut_group, Ruminiclostridium_5, Ruminococcaceae_UCG-005, and Ruminococcaceae_UCG-014 decreased. Compared with those in the NANP rats, mRNA expression of lysozyme and α-defensin5 and protein expression of lysozyme decreased significantly in the HANP rats. Moreover, in the NANP rats and the HANP rats, Allobaculum abundance was inversely correlated with lysozyme expression, while Anaerotruncus abundance was positively correlated with it by Spearman test. In conclusion, intestinal microbiota dysbiosis and decreased AMPs of Paneth cells might participate in the pathogenesis of intestinal barrier dysfunction in HANP.

Poly(ADP-ribose) polymerase inhibition suppresses inflammation and promotes recovery from adrenal injury in a rat model of acute necrotizing pancreatitis.

BackgroundPoly(ADP-ribose) polymerase (PARP) participates in multi-organ failure in various inflammatory diseases including acute necrotizing pancreatitis (ANP). Since pancreatitis-associated adrenal insufficiency is partly caused by inflammatory damage to the adrenal cortex, we examined whether PARP antagonism could alleviate adrenal insufficiency in a rat model of ANP.MethodsANP was induced by retrograde infusion of sodium taurocholate into the bile-pancreatic duct. At 30 min prior to taurocholate infusion, rats were pretreated with the PARP inhibitor 3-Aminobenzamide (3-AB, 20 mg/kg) or vehicle. Pancreatic pathological injury, adrenal histology, neutrophil infiltration, cell apoptosis, and serum corticosterone level were assessed at various times points. Activities of poly(ADP-ribosyl)ated protein (PAR), nuclear factor-kappaB (NF-kB), tumor necrosis factor-α (TNF-α), intercellular adhesion molecule-1 (ICAM-1) and inducible nitric oxide synthase (iNOS) in the adrenal were also examined.ResultsPARP overactivation in ANP rats is associated with reduced serum corticosterone level and marked cellular alterations in adrenocortical tissue. Inflammatory stress caused by ANP reduced adrenal corticosterone release. 3-AB reduced the activation of PARP and inflammatory markers, decreased myeloperoxidase activity, attenuated adrenal morphologic lesions and cells apoptosis, simultaneously improved the impaired adrenal function.ConclusionsOur data demonstrate the involvement of PARP overactivation in the pathogenesis of adrenal dysfunction after ANP. PARP inhibition may suppress inflammation and promote functional recovery from adrenal injury.

Paeoniflorin ameliorates acute necrotizing pancreatitis and pancreatitis‑induced acute renal injury.

Acute renal injury caused by acute necrotizing pancreatitis (ANP) is a common complication that is associated with a high rate of mortality. Paeoniflorin is the active ingredient of paeonia radix and exhibits a number of pharmacological effects, such as anti-inflammatory, anticancer, analgesic and immunomodulatory effects. The present study detected the potential treatment effects of paeoniflorin on acute renal injury induced by ANP in a rat model. The optimal dose of paeoniflorin for preventing acute renal injury induced by ANP was determined. Then, the possible protective mechanism of paeoniflorin was investigated. The serum levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 were measured with enzyme-linked immunosorbent assay kits. Renal inflammation and apoptosis were measured by immunohistochemistry and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. The expression of nitric oxide in kidney tissues was also evaluated. The p38 mitogen-activated protein kinases (MAPKs) were measured by western blotting. The results shown that paeoniflorin may ameliorate acute renal injury following ANP in rats by inhibiting inflammatory responses and renal cell apoptosis. These effects may be associated with the p38MAPK and nuclear factor-κB signal pathway.

Functional role of MicroRNA-19b in acinar cell necrosis in acute necrotizing pancreatitis.

The expression of microRNA-19b (miR-19b) in acute necrotizing pancreatitis (ANP) and its functional role in acinar cell necrosis of SD rats were investigated. Twelve SD rats were divided into two groups randomly, including control group and ANP group. The rat ANP models were established by intraperitoneal injection of L-arginine (2400 mg/kg body weight), and equal volume of 0.9% NaCl was injected in the control group. MiRNA chip assay was performed to examine the expression of miRNAs in the pancreas in two different groups. Besides, to further explore the role of miR-19b in ANP in vitro, taurolithocholic acid 3-sulfate disodium salt (TLC-S) (200 μmol/L) was administrated to treat the rat pancreatic acinar cell line, AR42J, for establishing the ANP cells model. The quantitative real-time PCR (qRT-PCR) was adopted to measure the miR-19b expression. Moreover, the mimic miRNA, miRNA antisense oligonucleotide (AMO) and control vector were used to transfect AR42J cells, the expression of miR-19b was confirmed by qRT-PCR and the necrotizing rate of AR42J cells was detected with AO/EB method. The expression of miR-19b was significantly higher in ANP group than in control group as displayed by the miRNA chip assay. Furthermore, after inducing necrosis of AR42J cells in vitro, the expression of miR-19b was significantly increased by 2.51±0.14 times in comparison with the control group. As revealed by qRT-PCR assay, the expression of miR-19b was 5.94±0.95 times higher in the mimic miRNA group than in the control vector group, companied with an obviously increased acinar cell necrotizing rate (50.3%±1.5% vs. 39.6%±2.3%, P<0.05). Moreover, the expression of miR-19b in the miRNA AMO group was 0.38±0.15 times lower than in the control vector group, and the cell necrosis rate was much lower accordingly (23.1%±3.3% vs. 39.6%±2.3%, P<0.05). Besides, there was no significant difference between the control vector cells and the cells without treatment (P>0.05). The expression of miR-19b was significantly induced in ANP. In addition, up-regulation of miR-19b could promote the necrosis of pancreatic acinar cells and miR-19b deficiency could decrease the rate of pancreatic acinar cell necrosis.

N-acetylcysteine amid reduces pancreatic damage in a rat model of acute necrotizing pancreatitis

BackgroundInflammatory explosion and oxidative stress are important mechanisms of injury in acute necrotizing pancreatitis (ANP). This study investigated the effects of N-acetylcysteine amid (NACA), a novel cell-permeant antioxidant with anti-inflammatory activity, on experimental ANP in rats. Materials and methodsFifty-two adult male Sprague–Dawley rats were used, and ANP was induced by cerulein. The animals were divided into four groups which were sham + saline, sham + NACA, ANP + saline, and ANP + NACA. NACA (2.2 mg/kg, i.p) was administered for 6 h, after the induction of ANP. The extent of acinar cell injury, mortality, systemic cardiorespiratory variables, functional capillary density, renal/hepatic functions, and changes in some enzyme markers for pancreas and lung tissues were investigated. ResultsInduction of ANP increased mortality from 0% in the sham group to 43.75% in the ANP + saline group (P < 0.05), and administration of NACA significantly reduced mortality to 12.5% (P < 0.05). Induction of ANP also caused increases in pancreatic necrosis, serum amylase, alanine aminotransferase (ALT), interleukin-6, LDH in bronchoalveolar lavage fluid, serum urea, tissue myeloperoxidase in pancreas and lung tissues and malondialdehyde. There was less pronounced increase in these parameters in NACA treated group. Compared with ANP group, ANP + NACA group had lower levels of pancreatic necrosis (0.5 ± 0.2 versus 1.45 ± 0.2, P < 0.05) and inflammation (0.6 ± 0.2 versus 1.29 ± 00.3, P < 0.05) scores. ConclusionsAdministration of NACA significantly decreased the ANP-induced mortality and also provided significant improvements in hemodynamic changes. The obtained positive effects of NACA on the course of pancreatitis indicates its potential usefulness in the management of ANP.

Decreased MIZ1 Expression in Severe Experimental Acute Pancreatitis: A Rat Study.

We tested our hypothesis that Myc-interacting zinc finger protein 1 (MIZ1), a cell cycle regulator, suppressed inflammation, and therefore, represented a useful prognostic marker in patients with acute necrotizing pancreatitis (ANP) complicated by acute lung injury. Sprague-Dawley rats were randomly divided into control and ANP groups at different time points. The MIZ1 protein expression was measured by Western blot and ELISA, and confirmed using immunohistochemistry. The severity of pancreatic and lung injury was evaluated by the injury score and wet/dry weight ratio. The severity of disease was evaluated by serum C-reactive protein (CRP). The MPO activity of lung tissue amylase levels and the degree of inflammation were evaluated by serum tumor necrosis factor (TNF)-α and interleukin (IL)-6 expression. The risk due to multiple factors was investigated by relationship analysis. The serum levels of CRP, amylase, TNF-α, and IL-6 were gradually increased at 6, 24, and 48 h in ANP when compared with the control rats. The MIZ1 expressions were greatly decreased in ANP rats, especially at 24 h. Statistical analysis showed that there were time-dependent differences in ANP rats when compared with control rats (6 vs. 24 or 48 h, P < 0.01). MIZ1 showed close negative correlation with the degree of pancreatic and lung injury, serum amylase, CRP, TNF-α, and IL-6 (P < 0.01, respectively). The decreasing MIZ1 expression was closely correlated with inflammatory response, and development of ANP. Decreasing MIZ1 levels indicate a risk for ANP.

Effects of glutamine alone on the acute necrotizing pancreatitis in rats

BackgroundThe effects of the glutamine on the acute pancreatitis are controversial in the clinical and experimental studies. The aim of this study was to investigate the influence of glutamine alone on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats. Material and methodsFifty-two male Sprague–Dawley rats weighing 300-350 g were used. Rats were divided into four groups as sham + saline, sham + glutamine, ANP + saline and ANP + glutamine. ANP in rats was induced by glycodeoxycholic acid. The extent of acinar cell injury, mortality, systemic cardiorespiratory variables, functional capillary density, renal/hepatic functions, and changes in some enzyme markers for pancreatic and lung tissue were investigated during ANP in rats. ResultsThe induction of ANP resulted in a significant increase in the mortality rate, pancreatic necrosis, and serum activity of amylase, alanine aminotransferase, interleukin-6, lactate dehydrogenase in bronchoalveolar lavage fluid, serum concentration of urea, and tissue activity of myeloperoxidase and malondialdehyde in the pancreas and lung, and a significant decrease in concentrations of calcium, blood pressure, urine output, pO2, and functional capillary density. The use of glutamine alone improved these changes. ConclusionsGlutamine demonstrated beneficial effect on the course of ANP in rats. Therefore, it may be used by itself in the treatment of acute pancreatitis.

Effect of Chaiqin Chengqi Decoction on cholecystokinin receptor 1-mediated signal transduction of pancreatic acinar cells in acute necrotizing pancreatitis rats.

To investigate the effect of Chaiqin Chengqi Decoction (,CQCQD) on cholecystokinin receptor 1 (CCKR1)-mediated signal transduction of pancreatic acinar cell in rats with acute necrotic pancreatitis (ANP). Twenty-seven Sprague-Dawley rats were randomized into three groups: the control group, the ANP group, and the CQCQD group (9 in each group). ANP rats were induced by two intraperitoneal injections of 8% L-arginine (pH=7.0, 4.4 g/kg) over a 2-h period. Rats were treated with 1.5 mL/100 g body weight of CQCQD (CQCQD group) or physiological saline (control and ANP groups) at 2 h interval. And 6 h after induction, pancreatic tissues were collected for histopathological examination. Pancreatic acinar cells were isolated for determination of CCKR1 mRNA and protein expression, phospholipase C (PLC) and inositol-1,4,5-triphosphate (IP3), and determination of fluorescence intensity (FI) as a measure of intracellular calcium ion concentration [Ca(2+)]i. The pancreatic histopathological score (6.2 ± 1.1) and the levels of PLC (1,187.2 ± 228.2 μg/mL) and IP3 (872.2 ± 88.4 μg/mL) of acinar cells in the ANP group were higher than those in the control (2.8 ± 0.4, 682.5 ± 121.8 μg/mL, 518.4 ± 115.8 μg/mL) and the CQCQD (3.8 ± 0.8, 905.3 ± 78.5 μg/mL, 611.0 ± 42.5 μg/mL) groups (P<0.05). [Ca(2+)]i FI for the ANP group (34.8±27.0) was higher than that in the control (5.1 ± 2.2) and CQCQD (12.6 ± 2.5) groups (P<0.05). The expression of pancreatic acinar cell CCKR1 mRNA in the ANP group was up-regulated (expression ratio=1.761; P=0.024) compared with the control group. The expression of pancreatic acinar cell CCKR1 mRNA in the CQCQD group was down-regulated (expression ratio=0.311; P=0.035) compared with the ANP group. The ratio of gray values of the CCKR1 and β-actin in the ANP group (1.43 ± 0.17) was higher than those in the control (0.70 ± 0.15) and CQCQD (0.79 ± 0.11) groups (P<0.05). Pancreatic acinar cell calcium overload of ANP induced by L-arginine was related to the up-regulated expressions of pancreatic acinar cell CCKR1 mRNA and protein. CQCQD can down-regulate expressions of pancreatic acinar cell CCKR1 mRNA and protein to reduce the PLC and IP3 of pancreatic acinar cells, relieving the calcium overload and reducing the pathological changes in rats with ANP.

Chaiqinchengqi decoction regulates necrosis-apoptosis via regulating the release of mitochondrial cytochrome c and caspase-3 in rats with acute necrotizing pancreatitis

ObjectiveTo explore the effect and the mechanism of Chaiqinchengqi decoction (CQCQD) on the apoptosis-necrosis switch of pancreatic acinar cells in acute necrotizing pancreatitis (ANP) in rats. MethodsSixty Sprague-Dawley rats were randomized into the control group, the ANP group and the CQCQD group. The acute pancreatitis (AP) model was induced by intraperitoneal injections of 4 g/kg 8% L-Arginine (PH 7.0) twice with a 1 h interval. Rats in the CQCQD group were intragastrically administered CQCQD (20 mL/kg every 2 h, 3 times, then 20 mL/kg every 6 h, 3 times). Rats were killed at the 6 and 24 h after the induction of AP. The pancreatic tissues were collected for pathology and to isolate pancreatic acinar cells and mitochondria. ResultsCQCQD significantly ameliorated the severity of ANP by reducing the pancreatic histopathology score, indicated by lactate dehydrogenase levels at the 6 and 24 h. The CQCQD group promoted the apoptosis of pancreatic acinar cells by raising the apoptosis index compared with the ANP group and the control group. Mitochondrial cytochrome c at the 6 and 24 h in the ANP group were lower than that in the control group or the CQCQD group (0.67±0.13 vs 1.54±0.03 vs 0.81±0.09; 0.71±0.08 vs 1.55 ± 0.09 vs 0.89 ± 0.16, P<0.01). The cytochrome c levels in the cytoplasm at the 6 and 2 h in the CQCQD group were higher than in the control group (1.36±0.15 vs 0.67±0.04, 1.46±0.08 vs 0.59± 0.09, P<0.01), or the ANP group (0.96±0.13, P>0.05; 0.97±0.09, P<0.05). CQCQD increased caspase-3 activity over the ANP group at the 6 h. ConclusionCQCQD can induce apoptosis and relieve the necrosis of pancreatic acinar cells via promoting the release of mitochondrial cytochrome c and increasing pancreatic caspase-3 activity in ANP rats.

Effects of 17ß-Estradiol on the Acute Necrotizing Pancreatitis after Onset in Rats

The aim of this study was to investigate the influence of 17ß-estradiol (E2) on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats. Rats were divided into six groups as sham + saline, sham + single dose E2 (SDE2), sham + multiple dose E2 (MDE2), ANP + saline, ANP + SDE2, and ANP + MDE2. ANP in rats was induced by glycodeoxycholic acid. The extent of acinar cell injury, mortality, systemic cardiorespiratory variables, functional capillary density (FCD), renal/hepatic functions, and changes in some enzyme markers for pancreatic and lung tissue were investigated during ANP in rats. The induction of ANP resulted in a significant increase in the mortality rate, pancreatic necrosis, and serum activity of amylase, alanine aminotransferase (ALT), interleukin (IL)-6, lactate dehydrogenase (LDH) in bronchoalveolar lavage (BAL) fluid, serum concentration of urea, and tissue activity of myeloperoxidase (MPO) and malondialdehyde (MDA) in the pancreas and lung, and a significant decrease in concentrations of calcium, blood pressure, urine output, p02, and functional capillary density (FCD). The use of E2 did not alter these changes. E2 demonstrated no effect on the course of ANP in rats. Therefore, it has no value in the treatment during acute pancreatitis.

Effects of Clotrimazol on the Acute Necrotizing Pancreatitis in Rats

This study aims to investigate the influence of clotrimazol (CLTZ) on acute necrotizing pancreatitis (ANP) induced by glycodeoxycholic acid in rats. Rats were divided into five groups as sham + saline, sham + CLTZ, sham + polyethylene glycol, ANP + saline, and ANP + CLTZ. ANP in rats was induced by glycodeoxycholic acid. The extent of acinar cell injury, mortality, systemic cardiorespiratory variables, functional capillary density (FCD), renal/hepatic functions, and changes in some enzyme markers for pancreatic and lung tissue were investigated during ANP in rats. The use of CLTZ after the induction of ANP resulted in a significant decrease in the mortality rate, pancreatic necrosis, and serum activity of amylase, alanine aminotransferase, interleukin-6, lactate dehydrogenase in bronchoalveolar lavage fluid, serum concentration of urea, and tissue activity of myeloperoxidase, and malondialdehyde in the pancreas and lung and a significant increase in concentrations of calcium, blood pressure, urine output, pO2, and FCD. This study showed that CLTZ demonstrated beneficial effect on the course of ANP in rats. Therefore, it may be used in the treatment of acute pancreatitis.

Expression of pancreatic regenerating gene in lung and intestinal tissue correlates with the severity of disease in rats with acute necrotizing pancreatitis

The aim of this study was to investigate the expression pattern of regenerating gene I (Reg I) in the lung and intestinal tissues of rats with acute necrotizing pancreatitis (ANP), as well as the correlation of Reg I expression with lung and intestinal injury. Sprague-Dawley rats were randomly allocated to control (n=40) and ANP (n=80) groups. The rats in the control group received laparotomy only. In the ANP group, 3% sodium taurocholate was injected into the pancreatic duct to develop the ANP model. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to detect the Reg I mRNA levels in the pancreas, intestine and lung. The pathological changes in the pancreas, intestine and lung were observed and the serum amylase levels, the wet/dry weight ratio of the lung and the permeability of the intestinal mucosa were measured. The measured parameters were found to correlate with the Reg I mRNA levels. Reg I mRNA was more highly expressed in the pancreas, intestine and lung in the ANP rats than in the control group. The Reg I expression levels were positively correlated with the pathological scores, serum amylase levels, lung pathological scores, lung tissue wet/dry ratios, intestinal pathological scores and intestinal permeability. The levels of Reg I were increased in the lung and intestinal tissue of the ANP rats and the expression levels of Reg I correlated closely with the severity of the lung and intestinal injury.

Down-Regulation of Aquaporin 1 in Rats With Experimental Acute Necrotizing Pancreatitis

The objectives of this study were to investigate the expression of aquaporin 1 in capillary endothelial cells of rats with experimental acute necrotizing pancreatitis (ANP) and to explore its pathogenic role in capillary leak. Sixty-four male Sprague-Dawley rats were randomly divided into control (n = 32) and ANP groups (n = 32). Eight rats in each group were killed at 3, 6, 12, and 18 hours after induction of experimental models. Quantity of ascites and levels of serum amylases were measured. Capillary permeability in pancreas, lung, and intestinal tissue was detected by Evans blue extravasation method. Aquaporin 1 expression in pancreas, lung, and intestinal tissue was detected by real-time polymerase chain reaction, immunohistochemical staining, and Western blot. Serum amylase level was significantly higher in ANP group than in controls (P < 0.05). Evans blue concentration in tissues in the ANP group was significantly higher than that in controls (P < 0.05). Aquaporin 1 mRNA and protein expressions in tissues were significantly less in the ANP group than in the controls (P < 0.05). The expression of aquaporin 1 was down-regulated in the pancreas, lung, and intestinal tissue of ANP rats, which could play an important role in the pathogenesis of capillary leak syndrome.

Expression of protease activated receptors-2 in intestinal mucosa of acute necrotizing pancre-atitis in rats

Objective To explore the correlation between the expression of protease activated receptors-2 (PAR-2) and intestinal mucosal barrier injury of acute necrotizing pancreatitis (ANP) in rats.Methods The ANP rat model was created.The expression of PAR-2 in rat's intestinal mucosa of sham-operated group and ANP group at six,12 and 24 hours after model established was detected by immunohistochemistry (IHC),reverse transcription-polymerase chain reaction (RT-PCR) and Western blot.The difference between groups was analyzed by one way analysis of variance.Results The results of IHC indicated that PAR-2 expression in rat's intestinal mucosa of sham-operated group was weak.The number of PAR-2 expression positive cells and immunostaining intensity increased significantly after ANP model established.The IHC score was 4.88±0.33,5.87±0.32 and 11.17±0.27 at six,12 and 24 hours after model established respectively.Compared with those of shamoperated group (2.86 ± 0.31),the differences were statistically significant (F=747.08,P＜0.01).The expression of PAR-2 at mRNA and protein level in intestinal mucosa of sham-operated group was very low.As time extended after ANP model established,both expression increased gradually.The PAR-2 mRNA was 0.56±0.03,0.69±0.03,1.05±0.05,and the protein was 0.28±0.02,0.35±0.03,0.69±0.04 at six,12 and 24 hours after model established respectively.Compared with shamoperated group,the differences were statistically significant at each time point (F=785.69,1177.82,both P＜0.01).Conclusions PAR-2 is activated in the inflammatory progress of ANP,and may play an important role in the pathogenesis and development of intestinal mucosa barrier injury in ANP. Key words: Pancreatitis,acute necrotizing; Intestinal mucosa; Receptors,proteinaseactivated; Disease models,animal

Does Nuclear Factor-Kappa B in Peripheral Mononuclear Cells Have a Prognostic Role during Acute Necrotizing Pancreatitis in Rats?

Aim: To investigate the prognostic role of nuclear factor-kappa B (NF-ĸB) activity in peripheral blood mononuclear cells (PBMNCs) during acute necrotizing pancreatitis (ANP) in rats. Methods: ANP was induced by an intravenous infusion of cerulein over 6 h superimposed on glycodeoxycholic acid (10 mmol/l) into the biliary-pancreatic duct for 10 min. The rats were divided into five groups and the first group served as the control. ANP was induced in the remaining groups, which were followed for 6, 12, 24 and 48 h. The mortality rate, serum amylase, alanine transferase (ALT), urea, creatinine and calcium, pancreatic histology, and NF-ĸB activity in PBMNCs were investigated. The NF-ĸB activity in PBMNCs was measured as two subunits of NF-ĸB, p50 and p65. Results: A significant increase in mortality rate, pancreatic damage, serum activity of amylase and ALT, urea and NF-ĸB p65 activity in PBMNCs were observed. There was a significant correlation between the mortality rate and pancreatic damage in conjunction with time, but there was no correlation between NF-ĸB p65 activity in PBMNCs and the mortality rate. Conclusion: The measurement of p65 levels of NF-kB in PBMNCs has no prognostic role during ANP in rats.