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Malfunctioning of the intestinal microcirculation secondary to severe acute pancreatitis (SAP) can cause injuries to the intestinal mucosal barrier, translocation of gut flora, and sepsis. The glycocalyx on the vascular endothelium helps maintain its normal function through multiple mechanisms, including regulation of vascular permeability and inhibition of intercellular adhesion. It is unknown that whether pancreatitis inflicts injuries to the intestinal mucosal barrier through damaging glycocalyx or stabilizing glycocalyx can be a potential therapeutic target in maintaining the integrity of the intestinal mucosal barrier during SAP. Injecting sodium taurocholate into the pancreatic duct of Sprague-Dawley rats induced SAP. Intestinal perfusion, changes in endothelial glycocalyx, and the associated molecular mechanisms were assessed by laser Doppler velocimetry, electron microscopy, and the levels of heparan sulfate, syndacan-1, and tumor necrosis factor-α (TNF-α) in the superior mesenteric vein. Protective effects of hydrocortisone treatment in the intestinal microcirculation during SAP were evaluated. Degradation of the glycocalyx in intestinal vascular endothelium developed 3 h after the onset of SAP in rats. By 12 h, significant reduction of intestinal perfusion was observed. The concomitant elevated levels of TNF-α in the superior mesenteric vein suggest that TNF-α is involved in the degradation of the glycocalyx. With the use of hydrocortisone, intestinal perfusion was improved and the degradation of glycocalyx was reduced. The degradation of glycocalyx is involved in the malfunction of the intestinal microcirculation. The massive release of TNF-α participates in this process and leads to glycocalyx degradation. Hydrocortisone may be a good therapy to prevent this process.

Purpose: To evaluate the effects of a subconjunctival injection of low-molecular-weight heparin-taurocholate 7 (LHT7) on corneal neovascularization (CoNV) in rats., Methods: Twenty-four Sprague-Dawley rats were divided into 4 groups of 6 animals each. Corneal centers were cauterized by the application of a silver/potassium nitrate solution for 8 seconds. Either 0.02 or 0.04 mL of 25 mg/mL of LHT7 (low- and high-LHT7 groups, respectively) was subconjunctivally injected on days 2 and 4 after the cauterization was done; 0.02 mL of 25 mg/mL of bevacizumab was injected into rats in the positive control group, with normal saline (NS) being administered to a negative control group. Digital photographs of the cornea were taken 1 and 2 weeks later to calculate the percentage of CoNV using the area of the neovascularized cornea. To compare the differences in CoNV between weeks 1 and 2, the change in CoNV was calculated by subtracting the percentage of CoNV at 1 week from that at 2 weeks., Results: The percentage of CoNV did not differ among the 4 groups either 1 or 2 weeks after the cauterization (P > 0.05). In all groups except the NS group, the percentage of CoNV significantly decreased at 2 weeks compared with that at 1 week (all P < 0.05). Moreover, the changes of CoNV in the high-LHT7 and bevacizumab groups significantly decreased compared with that in the NS group (all P < 0.05). Two corneal stromal hemorrhages occurred, 1 in each LHT7 group., Conclusions: Despite complications, including corneal stromal hemorrhage, subconjunctival injection of LHT7 attenuated CoNV after chemical cauterization.

Objectives: The outcome from acute pancreatitis depends on the severity of systemic complications. To be able to investigate mechanisms underlying the development of these systemic complications in acute pancreatitis in both wild-type and genetically engineered animal models, a mouse model of severe necrotizing pancreatitis was developed and characterized., Methods: Pancreatitis was induced by retrograde infusion of sodium taurocholate into the common bile duct in mice. After determining the optimum volume and concentration of taurocholate, the pancreatic damage and systemic inflammatory response were compared with those in cerulein-induced pancreatitis., Results: Pancreatic damage was higher in taurocholate pancreatitis than hyperstimulation-induced pancreatitis (24 hours: cerulein, 5.8 +/- 0.2 points; taurocholate, 14.8 +/- 0.8 points; P < 0.001) and mortality reached up to 60% within the first 24 hours after taurocholate administration. Pulmonary damage was detected, as measured by an increase in albumin in bronchoalveolar lavage fluid only in taurocholate-induced pancreatitis (12 hours: cerulein, 97.1 +/- 22.83 mg/g of protein; taurocholate, 234.0 +/- 32.7 mg/g of protein; P < 0.001). Furthermore, plasma interleukin 6 concentration was significantly elevated in mice with taurocholate-induced pancreatitis (12 hours: cerulein, 2.6 +/- 6.1 pg/mL; taurocholate, 2168.8 +/- 941.7 microg/mL; P < 0.001) as compared with all other groups., Conclusions: Taurocholate pancreatitis is a reliable model for severe necrotizing pancreatitis in mice with significantly greater pancreatic damage and systemic inflammatory response in comparison with cerulein-induced pancreatitis.

Introduction: Survivin is one of the inhibitors of the apoptosis family and has dual effects: antiapoptotic effect and regulation of the cell cycle., Aim: To show involvement of survivin in acute pancreatitis., Methodology: Acute necrohemorrhagic pancreatitis was induced in male Wistar rats by intraductal infusion of 4% sodium taurocholate., Results: By northern blotting, the survivin mRNA level was significantly increased at 36 hours and peaked at 48 hours after induction of acute pancreatitis. Survivin protein was found in cytoplasm of ductal cells by immunohistochemical analysis at 48-72 hours. It was also observed in nuclei of both acinar and ductal cells as well as infiltrating cells. Apoptotic cells were observed in pancreatic acinar cells. Survivin protein partially colocalized with 5-bromo-2'-deoxyuridine in some nuclei of ductal cells., Conclusions: We showed involvement of survivin in acute pancreatitis in rats. Survivin may have some roles in the regulation of pancreatic regeneration and proliferation as well as an antiapoptotic effect after acute pancreatitis.

Plasma and urine levels of trypsinogen activation peptides (TAP) reflect the severity of acute pancreatitis in experimental and clinical acute pancreatitis. In trypsin-taurocholate-induced pancreatitis in rats, the extrinsic bovine trypsin used for the induction of pancreatitis might influence on the TAP levels after induction of pancreatitis. The aim of the present study was to elucidate whether infused trypsin itself affects TAP levels in trypsin-taurocholate-induced pancreatitis. Rats were divided into three groups. In the pancreatitis group, acute pancreatitis was induced by a retrograde infusion of bovine trypsin and sodium taurocholate into the pancreatic duct. In the duct infusion group and peritoneal injection group, a mixture of bovine trypsin and trypsin inhibitor, ONO-3403, was infused into the pancreatic duct or the peritoneal cavity. Plasma and urine TAP concentration significantly increased in trypsin-taurocholate-induced pancreatitis but not in the duct infusion and peritoneal injection groups for 6 hours after the infusion of trypsin. Serum rat immunoreactive trypsin (IRT) and amylase significantly increased in the pancreatitis and duct infusion groups but not in the peritoneal injection group. Serum levels of bovine IRT in the pancreatitis group was significantly lower than those in duct infusion and peritoneal injection groups. In conclusion, an intraductal infusion of bovine trypsin itself into pancreatic duct does not influence the levels of plasma and urine TAP in trypsin-taurocholate-induced pancreatitis.

Recent studies provide significant evidence that cholecystokinin (CCK) is involved in the induction and development of acute pancreatitis in experimental animals. However, the results obtained with specific CCK-A (peripheral) receptor antagonists are still controversial. The present studies were undertaken to evaluate the involvement of endogenous CCK and the CCK-A receptors in the development of severe acute pancreatitis induced in Otsuka Long-Evans Tokushima Fatty (OLETF) rats that have a selective defect in the CCK-A receptor. Three models of severe acute pancreatitis were induced by retrograde intraductal infusion of 4% sodium taurocholate, by the closed duodenal loop, or by a single intraperitoneal injection of 500 mg/100 g body weight of L-arginine in OLETF rats and control Long-Evans Tokushima Otsuka (LETO) rats. Plasma CCK levels rose up to 4- to 14-fold over the preloading values after the onset of acute pancreatitis in all three models in both groups of rats. However, histologic alterations as well as the magnitudes of increase in serum amylase and lipase activity and the pancreatic wet weight were significantly less in the OLETF rats than those in the LETO rats. In addition, 72 h after the onset of arginine pancreatitis, massive destruction of pancreatic parenchyma with a significant reduction in serum amylase and lipase activities and pancreatic wet weight was observed in the LETO rats, whereas these changes were not seen in OLETF rats. These results suggest that endogenous CCK and CCK-A receptors play a role in the development of severe acute pancreatitis in rats.

Recent findings have suggested that oxygen-derived free radicals play an important role in the development and progression of acute pancreatitis. Therefore, the present study was designed to investigate whether metallothionein, a free radical scavenger, can protect against acute pancreatitis. Rats were injected intraperitoneally with zinc, followed by either an infusion of cerulein at 10 micrograms/kg for 4 h or a retrograde injection with 100 microliters/100 g body weight of 5% sodium taurocholate into the pancreaticobiliary duct, in order to induce acute pancreatitis. Zn administration significantly increased the levels of both metallothionein and reduced glutathione in the pancreas; the metallothionein levels reached a peak of 83-fold of normal levels after 24 h. The indications of acute pancreatitis, as well as the mortality, were improved by Zn treatment before the onset of acute pancreatitis. Immunohistochemical studies showed that metallothionein accumulated in the acini of the pancreas in the Zn-treated groups, and with strong staining around the periphery of the vacuoles in the group treated with both Zn and cerulein. These findings suggested that Zn increased both metallothionein and glutathione levels in the pancreas and exerted a beneficial effect against ceruleinor taurocholate-induced acute pancreatitis in rats.

The role of luminal bile salts (taurocholate) in regulation of rat pancreatic secretion was examined by studies on the effects of luminal stimulants on the pancreas during infusion of various concentrations of taurocholate into the duodenum of conscious rats. Rats with external bile and pancreatic fistulae were used. For 24 h before the experiment, pancreatic juice was excluded from the intestine but bile was continuously returned to the duodenum. From the beginning of the experiment, 8-200 mM of taurocholate was infused at a rate of 1 ml/h instead of returning the bile. Pancreatic juice was collected for a 2-h period and then 2 micrograms of pancreatic secretory trypsin inhibitor-61 (PSTI-61) (= monitor peptide) or partially purified putative CCK-releasing peptide from rat intestine (intestinal CCK-RP) was injected into the duodenum (1 ml/min). Continuous infusion of taurocholate maintained a constant rate of pancreatic secretion, except at a concentration of 8 mM, which resulted in a slight increase in pancreatic secretion. Both PSTI-61 and intestinal CCK-RP significantly increased pancreatic secretions during infusion of 20 or 40 mM taurocholate, but had no significant effect during infusion of 80 or 200 mM taurocholate. Therefore, higher concentrations of taurocholate in the intestine prevented the stimulatory effects of luminal stimulants, probably by preventing the latter from reaching CCK cells.

The possibility that gastrointestinal hormones influence biliary lipid secretion was studied further in chronic bile fistula dogs and subsequently in a patient with a balloon-occludable t-tube. After stabilization of bile flow in the dog by infusing 500 mg/hr sodium taurocholate, glucagon and insulin increased bile flow, decreased cholesterol output, and had no effect on phospholipid or bile salt output. Similarly, during reinfusion of bile in the human subject, glucagon increased bile flow, decreased cholesterol output and had no effect on bile salt output. Phospholipid secretion decreased, as had occurred at a lower bile salt infusion rate in the chronic bile fistula dog. These findings suggest that glucagon or insulin may play a role in regulating cholesterol secretion in dog and man, and that mechanisms other than simple dilution of micelles are operative.

The biliary excretion of two oral cholecystographic contrast agents, iocetamic acid and iopanoic acid, were compared during low and high taurocholate infusion rates. The pharmacokinetics of these compounds after intravenous infusion were studied in bile-fistula dogs using both indirect and direct pharmacokinetic techniques. The indirect multiple infusion technique, corrected for urinary excretion, provides a reliable estimate of the maximum biliary excretion rates of either contrast agent without necessitating the sampling of biliary output. The results indicate that taurocholate facilitates the biliary excretion of both agents. At both taurocholate infusion rates studied, the maximum biliary excretion rate of iocetamic acid is greater than that of iopanoic acid.