Mechanism of intestinal barrier functional disturbance in rats with severe acute pancreatitis

Abstract

Objective To investigate the mechanism of intestinal barrier functional disturbance in rats with severe acute pancreatitis (SAP). Methods Forty-eight Sprague-Dawley (SD) rats were randomly divided into SAP model group (SAP group, n=24) and sham operation group (SO group, n=24) according to the random number table method. SAP model was established in SAP group by retrograde injection of 3% sodium taurocholate in pancreatic duct. The intestinal canals of rats in SO group were only flipped after laparotomy. At the time points of 6, 12, 24 h after operation, the seroperitoneum volume of 8 rats in each group was measured after laparotomy and the inferior vena cava blood was collected to measure the levels of blood amylase, tumor necrosis factor (TNF)- α, D-lactic acid, diamine oxidase (DAO) . The tissues of pancreas and terminal ileum were pathologically examined after the rats were sacrificed. The experimental data of two groups were compared using t test. Results SAP model was established successfully in SAP group and seroperitoneum, increasing blood amylase, pathological damage of pancreatic tissues were observed in the rats. At the time points of 6, 12 and 24 h after operation, the average blood TNF- α levels in SAP group [(262±17), (320±18), (382±33) μg/L] were significantly higher than that in SO group [(201±16) μg/L] (t=10.066, 7.387, 7.720; P<0.05). Increasing intestinal permeability and alteration of intestinal flora were observed in SAP group. The blood D-lactic acid levels were (168±14), (200±15), (255±24) μg/L accordingly in SAP group and were significantly higher than that in SO group [(125±9) μg/L] (t=13.211, 25.191, 36.888; P<0.05). The blood DAO levels were (156±12), (196±11), (220±14) μg/L accordingly in SAP group and were significantly higher than that in SO group [(119±6) μg/L] (t=23.811, 43.561, 48.069; P<0.05). The ileum mucosa damage and local focal necrosis or piecemeal intestinal necrosis were observed in SAP group. The intact structure of ileum mucosa tissues were observed in SO group. Conclusion The activated TNF- α, alteration of intestinal flora and increasing intestinal permeability may play important roles in the intestinal barrier functional disturbance of rats with SAP. Key words: Pancreatitis, acute necrotizing; Bacterial translocation; Tumor necrosis factor- alpha; Lactic acid; Rats