Effective peritoneal therapy of acute pancreatitis in the rat with glutaryl-trialanin-ethylamide: a novel inhibitor of pancreatic elastase

Ulinastatin enhances the therapeutic effect of intraperitoneal lavage on severe acute pancreatitis in rats

The present study investigated the therapeutic effect of peritoneal lavage with ulinastatin on the outcome of rats with severe acute pancreatitis (SAP). A total of 110 male Wistar rats were randomly divided into the following groups: Control (C), SAP model (SAP), saline lavage (SL), intravenous ulinastatin (IU) and low-dose (LUL), medium-dose (MUL), high-dose (HUL) and ultrahigh-dose (UHUL) ulinastatin lavage. The treatments were performed immediately subsequent to the establishment of the SAP model. Intraperitoneal lavage with or without ulinastatin was performed for 3 h. Survival time was recorded for 12 h and the median survival time was calculated. Histopathological analyses, and measurements of plasma amylase and lipase levels were performed. Blood pH, lactic acid and base excess were also detected. The LUL, MUL, HUL, UHUL and IU groups showed an increase in the median survival time compared with the SAP group, with the maximal effect observed in the MUL group (P<0.01). The SL, MUL and IU groups showed a reduced activity of amylase and lipase compared with the SAP group. The SL (P<0.01) and the MUL groups (P<0.01) additionally showed a reduction in the lactic acid in arterial blood relative to the SAP group but the IU group did not. The MUL group showed greater improvements in pH (P<0.01) and base excess (P<0.01) versus the SAP group than the SL and IU groups. Furthermore the MUL group demonstrated a more marked reduction in the histological changes in necrosis, edema and inflammation compared with the SL and IU groups. Intraperitoneal lavage with ulinastatin significantly improves the prognosis of SAP in rats.

Early-phase peritoneal drainage and lavage in a rat model of severe acute pancreatitis

PURPOSE

To evaluate the effects of early-phase drainage on the survival rates and pancreatic pathological changes associated with severe acute pancreatitis (SAP) in a rat model.

METHODS

Sprague-Dawley rats were divided into the following groups: SAP model (control), early drainage and delayed drainage. The 24-h survival rates were compared among the groups. In addition, the serum and ascites concentrations of interleukin (IL)-1β, IL-6, IL-8, IL-10 and tumor necrosis factor (TNF)-α were measured, and pancreatic pathological changes were observed.

RESULTS

The survival rate significantly improved in the early drainage group. Compared with that observed in the control group, the serum TNF-α and IL-8 concentrations in the early drainage group decreased, while the serum IL-10 levels increased, and the ascites concentrations of IL-1β, IL-6, IL-8 and TNF-α decreased, while that of IL-10 increased significantly. In the delayed drainage group, only the ascites concentrations of TNF-α decreased. Meanwhile, the pancreatic pathological changes at 3, 6 and 24 h worsened in the early drainage group; however, the pancreatic lesions in the early drainage group were less mild than those seen in the control group.

CONCLUSIONS

Rebalancing the cytokine levels in ascites after early drainage may be a key factor for enhancing the survival rate in rats.

Early peritoneal lavage with ulinastatin improves outcome and enhances multi-organ protection in a model of severe acute pancreatitis

The aim of this study was to investigate the effect of early peritoneal lavage with ulinastatin on the outcome of a rat model of severe acute pancreatitis (SAP). A total of 80 male Wistar rats were randomly divided into the following groups: Sham-operated (C), SAP model (M), saline lavage (SL), intravenous ulinastatin (IU), early ulinastatin lavage (EUL) and late ulinastatin lavage (LUL). Intraperitoneal lavage or injection were performed immediately subsequent to the establishment of the SAP model in groups SL, IU and EUL and 3 h later in group LUL. Intraperitoneal lavage with or without ulinastatin was performed for 3 h. The survival time of the rats in groups C, M, EUL and LUL was recorded over a 12-h period and the median survival time was calculated. At 3 h after the induction of SAP, histopathological analyses were performed and the biochemical parameters of groups C, M, SL, IU and EUL were assessed. Groups EUL and LUL exhibited an increased median survival time compared with Group M, with the survival time of the rats in group EUL markedly longer than that in the group LUL rats. Group SL, IU and EUL rats were found to have reduced plasma activities of amylase, lipase, aspartate transaminase and alanine transaminase, with the biggest change observed in the group EUL rats. Furthermore, the intervention in groups SL and EUL was more effective at reducing creatinine and urea levels than that in group IU. Rats in group EUL exhibited a greater inhibition of the SAP-induced increase in troponin T levels than rats in groups SL and IU. The pathological severity scores of the pancreas, liver, kidney and lung in group EUL were significantly lower than those in groups M and better than those in groups SL and IU. In conclusion, early intraperitoneal lavage with ulinastatin significantly improves the median survival time and protects multi-organ function in an SAP model.

Prior peritoneal lavage with hot 0.9 % saline induces HSP70 expression and protects against cerulein-induced acute pancreatitis in rats

Recent studies have indicated that pre-induction of heat shock protein 70 (HSP70) expression in the pancreas protects against secretagogue-induced pancreatitis. In those studies, the HSP70 was mostly induced by unfeasible conditions. The aim of this current study was to investigate the effect of peritoneal lavage with hot 0.9 % saline (42 °C) on the pancreatic expression of HSP70 and its protective effect on cerulein-induced acute pancreatitis in rats. Male Wistar rats were peritoneally lavaged with 0.9 % saline at 42 °C for 30 min. HSP70 expression was evaluated by western blotting analysis. Prior peritoneal lavages with hot and warm saline were performed. Acute pancreatitis was induced by administration of intraperitoneal injection of cerulein (20 μg/kg) four times, and its severity was assessed by measuring serum amylase, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and trypsinogen activation peptide (TAP) levels. Pancreatic sections were stained with hematoxylin and eosin for histological evaluation. Peritoneal lavage with hot 0.9 % saline increased intrapancreatic HSP70 expression and ameliorated the cerulein-induced pancreatitis in rats, judged by the significantly reduced serum amylase, TNF-α, and IL-6 concentrations; histopathological scores, and serum TAP levels. Peritoneal lavage with hot 0.9 % saline can induce HSP70 expression and prevent cerulein-induced acute pancreatitis in rats. The results suggest that HSP70 protects against cerulein-induced pancreatitis by preventing proinflammatory cytokine synthesis and trypsinogen activation during acute pancreatitis.

Protective effect of a pancreatic elastase inhibitor against a variety of acute pancreatitis in rats

Protective effect of trifluoroacetyl-L-lysyl-L-alaninanilide hydrochloride (compound 1), a pancreatic elastase inhibitor, on three types of acute pancreatitis models was examined in rats. Mild, moderate and severe acute pancreatitis were induced by cerulein, the closed duodenal loop method and retrograde injection of a taurocholate plus trypsin solution into the pancreatic duct, respectively. Intravenous infusion of compound 1 at a dose of 30 mg/kg/hr resulted in lower increases in serum amylase, lipase, blood urea nitrogen (BUN) and creatinine levels in rats with mild cerulein-induced edematous pancreatitis. Compound 1 had no beneficial effect on pancreatitis in rats with moderate pancreatitis. In rats with severe pancreatitis, prophylactic treatment of compound 1 (30 mg/kg/hr) reduced both elevated serum BUN level and ascitic volume, and it histologically inhibited the extent of pancreatic edema and hemorrhage. These results suggest that pancreatic elastase is partially responsible for pancreatic edema and hemorrhage exhibited by rats with severe acute pancreatitis.

Effects of high-dose intraperitoneal aprotinin treatment on complement activation and acute phase response in acute severe pancreatitis

Forty-eight patients with severe acute pancreatitis were treated with intraperitoneal lavage in a double-blind randomized multi-center trial. One group (aprotinin group, n = 22) was also treated intraperitoneally with high doses of the protease inhibitor aprotinin. In the group not treated with aprotinin (control group), 6 patients were operated on because of pancreatic necrosis, compared with none in the treated group. Complement activation and the acute phase response were studied with measurements of anaphylatoxin C3a, C1 inhibitor (C1 Inh), interleukin 6 (IL-6), and C-reactive protein (CRP). The control group had higher plasma levels of C3a and lower levels of C1 Inh compared with the aprotinin group. The differences were statistically significant for C3a but not for C1 Inh. Both groups had high plasma levels of IL-6 and CRP. There were no differences between the groups in CRP levels, but the control group had higher IL-6 levels (not statistically significant) than the aprotinin group. This was caused by very high levels in the 6 patients operated on because of pancreatic necrosis, indicating that IL-6 could be a good plasma marker of pancreatic necrosis. The results also show that massive antiprotease treatment reduces complement activation, as illustrated by the lower C3a levels in the aprotinin group. The lower C1 Inh levels in the control group could have been caused by an increased consumption of the inhibitor.

High-dose intraperitoneal aprotinin treatment of acute severe pancreatitis: a double-blind randomized multi-center trial

A multi-center double-blind trial was performed on 48 patients with severe acute pancreatitis. All patients were treated with intraperitoneal lavage. One group (n = 22) was also treated with high doses of the protease inhibitor, aprotinin (Trasylol; Bayer AG, Leverkusen, Germany) administered intraperitoneally. Eight patients died, giving a total mortality of 16.6%. No difference was observed between the two groups. Altogether, 12 patients were operated on, corresponding to 25%. In the group not treated with aprotinin, 6 patients were operated on because of pancreatic necrosis, compared with none in the treated group. The difference was statistically significant. There were no significant differences between the two groups with regard to organ failure or other complications. It was concluded that aprotinin counteracts the development of pancreatic necrosis when given intraperitoneally in high doses to patients with severe acute pancreatitis, thus reducing the need for surgical intervention in these patients.