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Objective This study was to evaluate the effects of growth hormone (GH) on cell apoptosis of intestinal epithelium in acute necrotizing pancreatitis (ANP) rats.Methods Seventy-two SD rats were divided into three groups randomly: sham operation (SO) group, ANP group, and GH treatment group. GH-treatment group received subcutaneously 0 75?U/kg of GH. At 3?h, 6?h, 12?h, and 24 ?h after induction of ANP, the small intestinal specimens were harvested and apoptosis of intestinal epithelium was studied by DNA gel electrophoresis, FCM and TUNEL method. FasL and Bax protein expressions were detected by immunohistochemistry.ResultsThe ladder pattern on DNA gel electrophoresis presented in all time points of ANP group, but only seen in GH-treated group at 3h. Apoptotic percentage significantly increased in ANP group [(50?11)%,(80?9)%,(48?17)%,(50?10)%] as compared with SO group [(54?4)%, (28?6)%, (39?5)%,(29?11)%], all P
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Objective Some experimental results indicated that cyclooxygenase 2 (COX 2) was involved in the regulatory process of balance between cell apoptosis and multiplication. The present study was designed to investigate the effect of COX 2 on the course of pancreatic adenocarcinoma cell apoptosis and its possible signal pathway. Methods Apoptosis of pancreatic cancer cells (PC 3, highly expressed COX 2) induced by selective COX 2 inhibitor, Celebrex (IC 50 , 100 ?mol), was detected by using DNA gel electrophoresis, flow cytometry and electron microscopy. Expressions of apoptotic related genes mRNA, including bcl xl, bax, Survivin, were analyzed by reverse transcription polymerase chain reaction (RT PCR). Results Substantial apoptosis was induced by the treating PC 3 cells with Celebrex, as revealed by typical ladder pattern of DNA fragments under DNA electrophoresis, increment of apoptotic apportion, and apoptotic body under electron microscopy. Apoptotic inhibitory genes, bcl xl, bax, Survivin, were expressed in PC 3 cells, and were down regulated significantly by Celebrex in bcl xl and Survivin but not for bax. Conclusion Above findings suggest that the COX 2 pathway contributes to the apoptosis of pancreatic cancer cell, which may be via signal transduction of bcl xl and Survivin genes.
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Objective To investigate the deleterious effects of enterogenous endotoxemia on the course of acute pancreatitis in mice, and its possible mechanisms. Methods Sixty five C57BL/6 mice were assigned to 4 groups randomly, including acute edematous pancreatitis (AEP), lipopolysacchride (LPS), AEP plus LPS and normal control. AEP was induced by intraperitoneal injection of cerulein with a dosage of 50 ?g/kg at hourly interval for seven times under ether anesthesia. LPS was administrated via a gastric tube with a dosage of 5 mg/kg at 6 h after the first cerulein or saline injection. Serum amylase and LDH activities were measured at 12 h, 24 h, 48 h and 5 d. Pathological alteration in pancreas was studied. Expressions of Mac 1 (CD11b/CD18), P selectin, E selectin and ICAM 1 were evaluated by using inmmunohistochemical procedures. Expressions of cytokine genes were determined by means of RT PCR and Southern blot. Myeloperoxidase (MPO) activity in pancreas was also analyzed. Results Cerulein induced a typical changes of AEP in mice, which was confirmed by pathological changes and hyperamylasemia. LPS alone didn't develop either morphological changes or biochemical alterations. However, cerulein induced AEP challenged by LPS could cause marked parenchymal necrosis and hemorrhage with significant increment of serum amylase and LDH activities. Expressions of Mac 1, P selectin, E selectin and ICAM 1 in pancreas were enhanced. Cytokine genes including TNF?,IL 1?,IL 6 and IFN? mRNA were also upregulated. MPO activity was increased. Conclusion This study suggested that enterogenous endotoxemia, which could not induce pancreatic injury per se , could induce AEP into ANP in mice. Over stimulation of neutrophils and releasing of pro inflammatory mediators might be the contributing factors.
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Objective To investigate whether apoptosis of intestinal epithelial cells occurs at the early stage of acute necrotizing pancreatitis (ANP) in rats. Methods Fourty eight Spraque Dawley rats were used. ANP model of rats was induced by retro injection of 5% sodium taurocholate into biliopancreatic duct. Laparotomized animals without induction of ANP (sham operation) served as controls. The distal segment of ileum specimens were harvested at 3 h, 6 h, 12 h and 24 h after operation and the apoptosis of intestinal epithelial cells was studied by DNA gel electrophoresis, FITC conjugated annexin V and propidium iodide (PI) staining cells analyzed by Flow Cytometry (FCM) and immunohistochemical procedures (TUNEL method). Results The DNA electrophoresis showed that typical “ladder” patterns appeared at all indicated time points in ANP group, while the DNA specimens from control group presented a single chromosomal lane, except the one at 12 h. Apoptotic percentage of detached intestinal epithelial cells assayed using Annexin V kit by FCM were (53.7?3.7)%, (27.6?6.0)%, (39.0?4.8)%, (29.0?11.3)% at 3 h, 6 h, 12 h and 24 h in control group and (50.3?11.3)%, (79.7?9.2)%, (47.8?17.3)%, (49.6?9.5)% in ANP group. There was a significant difference between two groups at 6 h, P