A. Kolettas, Georgia Lazaraki, E. Eleftheriadis, Katerina Kotzampassi, D. Paramythiotis,Hepatic ischemia/reperfusion-induced injury is accompanied by free radical production, leading to endothelial cell destruction, adhesion of neutrophils and plugging of the hepatic sinusoids and thus to blood microcirculation flow reduction. Naloxone is a known opioid antagonist that has been shown to act by inhibiting the release of free radicals. The purpose of this study is to clarify the changes in hepatic microcirculation during liver ischemia and after reperfusion in the rat and the potential beneficial effects of Naloxone as pretreatment, in respect to microcirculation and oxidative stress. One hundred and forty male Wistar rats, allocated to Naloxone [N] or Placebo [P] treatment, were subjected to either 30min or 60min normothermic ischemia [70% of total liver], followed by 60min reperfusion. Liver microcirculation was assessed by laser-Doppler flowmetry at baseline, at the end of the ischemia period [30min or 60min, respectively] and at the end of the reperfusion period, while oxidative stress was assessed by means of MDA at the same time periods. Naloxone pretreatment seemed to protect liver parenchyma, since MDA levels were significantly decreased in relation to placebo treated rats, in both 30min ischemia/ 60min reperfusion and 60min ischemia/60min reperfusion groups. Similarly, Naloxone pretreatment was found to significantly improve liver microcirculation in relation to placebo treated rats, in both groups. In conclusion, the results of this study indicate that Naloxone pretreatment protects the liver from ischemia/ reperfusion hepatocellular injury. Key words: Naloxone, ischemia/reperfusion injury, liver, laser- Doppler flowmetry, malondialdehydeapplication/pdfhttp://www.annalsgastro.gr/index.php/annalsgastro/article/view/353engHellenic Society of Gastroenterology1792-74631108-7471Annals of Gastroenterology; Volume 18, No 4 (2005)Naloxone: a potent protective agent in ischemia – reperfusion – induced liver injuryinfo:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersion2007-03-19Δημοσίευση σε περιοδικόPublication in journalΓαστροεντερολογίαGastroenterologyisi -Gastroenterology & Hepatology covers resources on the anatomy, physiology, biochemistry, and pathology of the digestive system. This category includes specific resources on the prognosis and treatment of digestive diseases; stomach ulcers; metabolic, genetic, infectious and chemically induced diseases of the liver; colitis; diseases of the pancreas and diseases of the rectum.Επιστημονικό άρθροScientific articleΕλληνική Γαστροεντερολογική ΕταιρίαGreek Aggregator OpenArchives.gr | National Documentation Centre (EKT)other