Caerulein-induced histopathological changes acude pancreatitis and the effects of pentoxifylline, L-arginin and Nω-nitro-L-argının methyl ester on these changes

11. SUMMARY Acute pancreatitis is an inflammatory disease characterised by pancreatic tissue oedema, aciner cell damage, haemorrhage and inflammation of the pancreas. Supramaximal stimulation of the pancreas a cholecystokinin analog; caerulein causes acute oedematous pancreatitis. Nitric oxide (NO) is a biological mediator that has been implicated in many physiological and pathophysiological processes. It may have a significant influence on the course of acute pancreatitis and the recovery process. Pentoxifylline, a methylxanthine derivative with rheologic and marked anti-inflammatory properties, inhibits the production of proinflammatory cytokines. The aim of the study was to investigate the effects of NO and pentoxifylline of caerulein-induced acute pancreatitis. In this study, 42 adult male Sprague Dawley rats, were randomly assigned to 6 groups as follows: 1- Control group. 2- Vehicle group: The rats from this group received %0.9 NaCI at a dose of 0.5 ml. 3- Caerulein grup: The rats received caerulein at a dose of 100 jitg/kg 4- Caerulein+L-Arginin group: The rats received caerulein at a dose of 100 p.g/kg and L-Arginin at a dose of 160 mg/kg. 5- Caerulein+L- NAME group: The rats received caerulein at a dose of 100 |^g/kg and L- NAME at a dose of 20 mg/kg. 6- Pentoxifylline groups: The rats received caerulein at a dose of 100 i^g/kg and pentoxifylline at a dose of 12 mg/kg. All rats were decapitated 12 hours after the last injection of caerulein and their pancreas were removed. Tissue samples were fixed in %10 notral buffered formalin and/or Bouin fixatives, and were embedded in paraffin. Sections were stained with Hematoxylin-eosin, Gomori's trichrome and Periodic acid Schiff. Prominent interstitial oedema, inflammatory infiltration, cytoplasmic vacuolation, degeneration and apoptosis were observed in caerulein group. Treatment with L-arginin and pentoxifylline markedly reduced these histological alterations. We conclude that, L-arginin and pentoxifylline may have beneficial effects in the treatment of caerulein-induced acute pancreatitis. Key words: Nitric oxide, pentoxifylline, acute pancreatitis, rat, microscopy 68