To examine the significance of a disturbed lymph drainage for the pathogenesis of acute necrotizing pancreatitis, thoracic duct ligation was performed in 53 Wistar rats. Histological examination of the pancreas and analysis of serum lipase and serum amylase were carried out at various time intervals from 1 h to 42 days after initiating the experiment. Sudden stop of the lymph flow induced a long lasting pancreatic edema, initially in the perilobular interstitium and eventually also within some lobules, with scattered necroses of whole acini or single acinar cells mainly in the peripheral zones of the lobuli. In addition, a marked interstitial inflammatory infiltrate developed, resembling lipophage granulomas. This was most likely due to alymphangeal reflux of sunflower oil, applicated for the visualization of the thoracic duct. These findings suggest that changes in the lymph flow may favour the development of acute necrotizing pancreatitis.