The effects of ischemic postconditioning on a rat model of hepatic ischemia and reperfusion injury

SHORT HEAD AND SUMMARYThe Effects of Ischemic Postconditioning on a Rat Model of Hepatic Ischemia andReperfusion InjuryBaki AYDOĞAN, MD.Dokuz Eylul University Department of Surgery, Inciraltı, Izmir - TURKEYHepatic pedicule clamping (Pringle maneuer) in major liver surgery results ischemia andreperfusion (I/R) injury. The method of ischemic preconditioning which is composed of short periodsof ischemia and reperfusion may be used for several times for preventing I/R injury. Recently, toprevent I/R injury another method, ischemic postconditioning, is proposed which is the application ofshort periods of I/R during reperfusion after a period of long lasting ischemia.The aim of this study is to evaluate the effects of ischemic preconditioning andpostconditioning on preventing the hepatic ischemia and reperfusion injury.The study was designed in five groups: Group 1 (n=4), sham rats; Group 2 (n=14), hepaticischemia and reperfusion; Group 3 (n=14), ischemic preconditioning and hepatic ischemia group;Group 4 (n=14), hepatic ischemia and ischemic postconditioning group; Group 5 (n=14), ischemicpreconditioning, hepatic ischemia and ischemic postconditioning group.Ischemia and reperfusion was performed by 60 minutes hepatic ischemia following 120 minutesreperfusion; ischemic preconditioning was performed by 10 minutes ischemia and 10 minutesreperfusion before 60 minutes hepatic ischemia; and ischemic postconditioning was performed by 60minutes hepatic ischemia followed by 2 minutes ischemia periods and between this periods inincreasing duration of reperfusion (2, 3, 5 and 7 minutes) periods.The protective effects on I/R injury was assessed in 2nd hour and 7th day of hepatic ischemia andserum liver enzymes, liver tissue malondialdehite and histopatological analysis were carried out.In our study, we observed that ischemic postconditioning do not protect hepatic I/R injury;moreover we observed an increase I/R injury with ischemic postconditioning. The effect of ischemicpreconditioning on hepatic I/R injury is superior to the effects of both ischemic preconditioning andpostconditioning.1