Time-course changes in pancreatic laboratory and morphologic parameters in two different acute pancreatitis models in rats
Takács, T.; Czakó, L.; Jármay, K.; Hegyi, P.; Pozsár, J.; Marosi, E.; Pap, A.; Lonovics, J.
Acta Medica Hungarica 50(1-2): 117-130
1994
ISSN/ISBN: 0236-5286 PMID: 7543670 Document Number: 423541
The aim of this work was to study in rats the temporal course of laboratory parameters and morphologic features in acute pancreatitis induced by cholecystokinin octapeptide (CCK-8) or by a closed duodenal loop. Pancreatitis was induced either with an overdose of CCK-8 (3 times 75 mu-g/kg at 1 h intervals) or by ligation of the duodenum on both sides of the bilio-pancreatic duct. The animals were examined at 0, 2, 4, 8, 16 and 24 h after AP induction. In CCK-8-induced acute pancreatitis, the pancreatic weight/body weight ratio (8.2 +- 1.1 mg/g) and the amylase level (44.8 +- 7.5 times 10-3 U/ml) were significantly increased vs. the controls (4.5 +- 0.8 mg/g and 3.3 +- 0.2 times 10-3 U/ml, respectively) 2 h after the intervention. The plasma CCK was significantly increased at 4 h (4.55 +- 1.7 pM) and remained elevated thereafter. The tissue malonyldialdehyde concentration was significantly elevated at 8 h (0.28 +- 0.07 mu-mol/mg pancreas) vs. the controls (0.20 +- 0.02 mu-mol/mg pancreas). In closed duodenal loop-induced acute pancreatitis, the ratio pancreatic weight/body weight steadily increased during the study; it reached its maximum level at 24 h (7.1 +- 0.5 mg/g) vs. the sham-operated control (4.8 +- 0.9 mg/g) . The serum amylase level was significantly elevated at 2 h (47.1 +- 9.3 times 10-3 U/ml), and then decreased steadily. Plasma CCK values were significantly higher than the controls throughout the study. A significant increase in the tissue malonyldialdehyde concentration (0.94 +- 0.15 mu-mol/mg vs. 0.20 +- 0.01 mu-mol/mg pancreas) appeared at 4 h. Our data indicate that in CCK-8-induced acute pancreatitis the laboratory signs of pancreatitis are most expressed at 4 h, whereas the morphologic changes culminate 8 h, following the last CCK injection. In closed duodenal loop-induced acute pancreatitis, the histologic findings showed a progressive deterioration. Endogenous CCK and oxygen-derived free radicals seem to play a role in the pathogenesis of both types of acute pancreatitis.