【Abstract】 Objective To investigate the effect of verapamil on apoptosis, calcium and expressions of bcl-2 and c-myc of pancreatic cells in ischemia-reperfusion rat model. Methods Wistar rats were randomly divided into three groups: control group （n=10）; ischemia-reperfusion group （n=10）; verapamil treatment group （n=10）. The anterior mesenteric artery and the celiac artery of rats in both ischemia-reperfusion group and verapamil treatment group were occluded for 15 min followed by 12-hour reperfusion. Verapamil （1 mg／kg） was injected via caudal vein to the rats in verapamil treatment group 15 min before occlusion and 1 hour after the initiation of reperfusion, respectively; and ischemia-reperfusion group was given the same volume of salient twice intravenously. Pancreatic tissues were collected from the dead rats after twelve hours since the reperfusion. The pathologic characters of pancreatic tissue were observed under light microscope; The level of calcium in the tissue was measured by atomic absorption spectrometer; TUNEL was used to detect apoptosis of pancreatic cells; and the expressions of c-myc and bcl-2 in the cells were also analyzed by immunohistochemistry technique and flow cytometry. Results The pathologic change in verapamil treatment group was less conspicuous than that of ischemia-reperfusion group. Both the calcium level and the number of apoptotic cells in verapamil treatment group were less than those of ischemia-reperfusion group 〔（411.1±55.8） μg/g dry weight vs （470.9±31.9） μg/g dry weight, P＜0.05 and （9.5±2.9）% vs （18.4±3.1）% 〕, P＜0.05. After taking verapamil, the number of apoptotic cells decreased, whereas the expressions of bcl-2 and c-myc increased. The fluorescent indexes of bcl-2 and c-myc in verapamil treatment group were significantly higher than those of ischemia-reperfusion group (1.72±0.11 vs 1.41±0.07, P＜0.05; 1.76±0.19 vs 1.55±0.13, P＜0.05. Conclusion Ischemia-reperfusion injury can induce apoptosis of pancreatic cells. Verapamil could protect the injured pancreatic tissue by reducing the level of calcium, stimulating the expressions of bcl-2 and c-myc and inhibiting apoptosis of pancreatic cells.
ObjectiveTo investigate the clinical significance of abnormal confluence of common bile duct (CBD) and pancreatic duct. MethodsFortyfive cases of biliary pancreatic confluence portion of cadavers were dissected and observed with microscope. ResultsThe lower end of CBD inserted normally into the medial posterior portion of descending duodenum with oblique angle (41.4±5.3)° and safeguarded by the sidelong wrinkle formed by mucous membrane of duodenum. In common, pancreatic duct ampulla inserted into CBD with oblique angle (28.5±7.9)° and jointed CBD in the medial wall of dudenum. The length ampulla of Vater was about 0.5-1.5 cm. The Vater’s ampulla was dilated obviously. ConclusionThe result indicates that pancreatic duct and CBD joint with a sharp angle. A number of abnormal anatomic factors may change the relation of oblique angle, and lead to the pancreatitis.
Objective To establish a rat model of pancreas-duodenal transplantation for pancreas transplantation research. Methods A rat model of pancreas-duodenal transplantation was established by using dual cuff technique. The graft affiliated portal vein and abdominal aorta were anastomosed to recipient’s left renal vein and left renal artery by using dual cuff technique without clamping the systemic circulation in order to minimize hemodynamic instability. Simultaneously the graft duodenum was anastomosed to the host jejunum in an end-to-side fashion to reestablish drainage of pancreatic secretion. Fluid replacement, warm keeping and anticoagulation were maintained during perioperative period. Results The average donor operation time was (68.4±7.2) min and recipient operation time was (26.1±3.3) min. Moreover, it took (5.0±1.1) min for cuff preparation in vitro and (9.6±3.5) min for vessel reconstruction in vivo, respectively. Intestinal anastomosis took (7.2±2.3) min. The operation successful rate was about 91.7%. Conclusion This pancreas-duodenal transplantation model avoids systemic circulation clamping. It is simple and stable, with the value in pancreas transplantation research.
Objective To summarize the advancement of immune tolerance in pancreas transplantation.Methods Relevant literatures about immune tolerance in pancreas transplantation, which were published recently domestic and abroad were collected and reviewed. Results The main methods to induce immune tolerance are peripheral tolerance and central tolerance. The induction of chimerism by infusion of donor-specific bone marrow cells is the research hot spot recently. Conclusion The infusion of donor-specific bone marrow cells in combination with one or more peripheral tolerance maybe can induce immune tolerance successfully. However, it should be researched further.
Objective To evaluate the imaging features of pancreatic neuroendocrine carcinoma （PNEC）. Methods The imaging data of 7 patients with PNECs proved by surgery and pathology in West China Hospital of Sichuan University from Jul. 2007 to Dec. 2012 were retrospectively analyzed. The boundary， density， and strengthening features of tumor were observed. Results Seven tumors were found in all patients with 2 in pancreatic head， body， and tail， respectively. There was 1 tumor in pancreatic body and tail too. Five tumors were with unclear boundary. Five tumors had hypodense enhancement and 2 had isodense enhancement. Two cases had distal pancreatic duct dilation. None of them had liver metastases or lymph node involvement. Conclusion PNEC has certain characteristics on imaging. It is difficult to distinguish diagnosis from pancreatic cancer.
Objective To investigate the roles of cell apoptosis and the gene expressions of Fas, FasL, bcl-2 and bax in acute rejection of pancreaticoduodenal transplantation and to evaluate the function of duodenum biopsy for early detection of rejection in rats. Methods Wistar and SD rats were divided into two groups: ①Wistar rats that underwent allogenic pancreaticoduodenal transplantation from the organs of SD rats; ②Wistar rats that received homogenic transplantation. The grafts were then harvested on day 3, 5 and 7 after the transplantation, and all graft samples were observed with HE staining and TUNEL was also used to detect apoptotic cells. The expressions of Fas, FasL, bcl-2 and bax were measured by immunochemical method. According to Nakhleh’s score, pathologic features of transplanted pancreas and duodenum were ranged from one to three scores in order. Results The percentage of same or different scores between the pathological scores of pancreas and duodenum in allogenic pancreaticoduodenal transplantation group were 61.1% (11/18) and 38.9% (7/18) respectively, and there were 6 specimens of pancreatic tissue got higher scores with only one higher score for duodenum. There were significant differences of histopathologic rejection scores and apoptotic indices between the two groups, respectively (P＜0.05， P＜0.01). Apoptotic indices of pancreas and duodenum both showed positive correlations with histopathologic rejection scores (r=0.965， P＜0.01; r=0.942, P＜0.01). The rejection score and apoptotic index elevated, the expression of FasL increased, bcl-2 decreased, and Fas and bax changed over time after operation. Conclusion Apoptosis maybe significantly positive correlated with the degrees of damage of the acute pancreaticoduodenal allograft rejection, and the apoptotic index maybe valuable to estimate the damage. FasL and bcl-2 were significantly related to the impairment of acute pancreatic allograft rejection as well. Duodenum biopsy may contribute to the early diagnosis of the rejecting transplanted tissues.
In order to avoid lesion of adjacent organs which were often occurred after routine cryotherapy of pancreanoduodinal area, a new cryosurgical method of isolated pancreano-duodinal area was designed for treatment of neoplasm in this area, the feasibility of this method was tried in four pigs.After bile common duct, tail of pancreas, stomach, and jejunum were divided and protected by dry cotton pad, the isolated pancreano-duodinal area was twice fozen to -170℃, maintaining ten minutes with LCS 2000 cryogenic surgical system, then alimentary tract was reconstructed with cholecystojejunostomy and gastroenterostomy. Animals were observed for 1-4 weeks. There was only transient elevation of amylase postoperation and the liver function and blood sugar remained normal. No any complication was seen except a small pseudocyst in lesser omentum. Thorough destruction of pancreatic tissue by enough deep and time course of cryotherapy was emphasized and some technic problem also were discussed. Based on our experiment, cryosurgery of isolated pancreano-duodenum will be considered as a safe and effect therapy of pancreano-duodinal neoplasm.
ObjectivesTo explore the mechanisms by which ischmic preconditioning (IPC), ischemic postconditioning (IPO) and IPCIPO exert influence on ischemic reperfusion injury (IRI) of the graft of SD rat after pancreas transplantation. MethodsAfter the establishment of diabetic SD rats model by using streptozotocin, 24 rats suffered from pancreas transplantation and were randomly averagely divided into four groups: I/R group, IPC group, IPO group, and IPC-IPO group. Six diabetic SD rats suffered with sham operation were served as SO group. The blood glucose level of rats in each group was detected before and after reperfusion, the contents of malonaldehyde (MDA) and super oxide dismutase (SOD) of pancreas allograft were tested at 2 h after reperfusion, and the apoptosis index (AI) of pancreas allograft was monitored by using TUNEL method. ResultsThe blood glucose level of rats in each group was not significantly different (Pgt;0.05). In SO group, the blood glucose level of rats was significantly higher than other groups (Plt;0.01). The blood glucose levels of rats after reperfusion decreased from the levels before reperfusion in I/R group, IPC group, IPO group, and IPC-IPO group (Plt;0.05 or Plt;0.01), furthermore the blood glucose level of rats in I/R group was significantly higher than that in abovementioned three groups (Plt;0.01), although among which the difference was not markedly (Pgt;0.05). When compared with I/R group, the MDA contents of rats after reperfusion in IPC group, IPO group， and IPC-IPO group decreased (Plt;0.01), while the SOD contents of rats after reperfusion increased (Plt;0.01). In rats of SO group, the MDA and SOD contents were significantly higher and lower than other groups, respectively (Plt;0.01). The MDA and SOD contents in IPC group, IPO group, and IPC-IPO group were not different (Pgt;0.05). The AI of pancreas allograft at 2 h after reperfusion in I/R group 〔(47.31±4.52)%〕, IPC group 〔(26.25±3.17)%〕, IPO group 〔(24.73±3.62)%〕, and IPC-IPO group 〔(25.5±4.15)%〕 were higher than that in SO group 〔(3.16±0.53)%〕, Plt;0.01. The AI of pancreas allograft in IPC group, IPO group, and IPC-IPO group were not different (Pgt;0.05), but they were lower than that in I/R group (Plt;0.01). Pathological results showed that injury of pancreas allograft in I/R group was most severe. ConclusionsIPO and IPC are associated with comparable effectiveness to protect graft from IRI during pancreas transplantation. The combined protective effects of IPC and IPO do not appear to be additive, which is equal to IPC or IPO alone.
ObjectiveTo explore the effect of endotoxin on insulin secretion from islet βcell of rat pancreas.MethodsAfter the model of endotoxemia was established in rats with intraperitoneal injection of LPS (2 mg/kg),the changes of insulin level in the serum and pancreas were dynamically determined, the expression of inducible nitric oxide synthase (iNOS) by situ hybridization and DNA damage in islet cells were also observed, the effect of sodium nitroprusside (exogenous NO) on synthesis and secretion of insulin from isolated islet βcell of normal rat pancreas under high glucose stimulation was also evaluated.ResultsThe level of glucose and insulin in plasma were significantly increased at 12th and 6th h, respectively and kept on 3 d after injection of LPS,but the insulin level in pancreas was not remarkably altered.The expression of iNOS and DNA damaged significantly enhanced at 6 d after endotoxemia. The high glucosestimulated insulin synthesis and secretion were bly inhibited by exogenous NO.ConclusionThese findings suggest that LPS be stimulate the expression of iNOS and NO product,which inhibites synthesis and secretion of insulin in islet βcells,but it stimulates insulin secretion by another mechanism,and results in dysfunction and destruction of the rat pancreas.
Objective To review the general approaches in isolation and purification of pancreatic islets and progress in several aspects. Methods The latest l iterature concerning acquisition of pancreatic islets was reviewed and analyzed interms of the choice of pancreatic islet donors, the digestion and isolation of pancreas, the purification of islet and the assay of outcome. Results The profile of the isolation and purification depends on the selection of reagents and methods of operation in every step and l inkup between every step. Conclusion Pancreatic islet transplantation is the most effective method to treat type 1 diabetes, the problem of inadequate sources of pancreatic islets could be resolved by the optimal process and the establ ishment of standardized operation.