The morphology of acinar cells during acute pancreatitis in rats induced by intraductal infusion of peracetate.

Many experimental models have been created to explain the pathophysiology of acute pancreatitis (AP). Investigations have been undertaken in this laboratory into the influence of strong oxidants introduced into the pancreas retrogradely through the bile-pancreatic duct. In these experiments a potentially toxic metabolite of ethanol-peracetic acid was used to induce AP. Wistar rats were treated with 1 mM and 40 mM peracetate and with a solvent as a control for 1 and 3 hours respectively. After a period of observation the samples of pancreata were examined in a light and electron microscope together with the content of sulphydryl groups as a marker of intracellular oxidative stress. The morphological examination showed profound changes in the histology of the pancreas and also in its subcellular structures, especially in groups 3 and 4 (with a higher concentration of peracetate). The changes included parenchymal haemorrhage and widespread acinar cell necrosis. The level of the sulphydryl groups decreased in the rats treated with peracetate. This suggests that the severity of the disease strongly depends on the intensity of the oxidative stress. The results confirmed the axial role of oxygen-derived free radicals in the pathogenesis of AP.