Effect of methylene blue on liver ischemia-reperfusion injury in rabbits / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effect of methylene blue(MB)on liver ischemia-reperfusion (I/R) injury in rabbits.Methods Twenty-four healthy New Zealand white rabbits of both sexes welshins 2.0-2.3 kg were randomly divided into 3 groups (n=8 each)group Ⅰ sham operation(group s);group Ⅱ I/R and group Ⅲ methylene blue (group MB).The animals were anesthetized with intravenous 2% pentobarbital 30 mg/kg.Liver I/R was produced by occlusion of hepatic blood flow for 40 min followed by 60 min repeffusion.In group MB methylene blue 5 mg/kg was injected iv at 20 min before liver ischemia.Femoral artery was carmulated for MAP monitoring and blood sampling.MAP and HR were recorded immediately before(T1,baseline)and at 20 and 40 min of ischemia (T2,3) and 1,5,30,60 min(T4-7)of repedusion.Blood samples were collected at T1,T5,T6 and T7 for measurement of seruln TNF-α and IL-6 concentrations.Plasma AST and ALT activities were measured at T1,T6 and T7.Liver specimens were obtained at the end of experiment for determination of SOD activity and MDA content.Results In group I/R MAP was significantly decreased at T4-7 during reperfusion and HR at T7 as compared with the baseline at T1;while in group MB no significant change in MAP and HR Was observed during ischemia and reperfusion as compared with the baseline.The gerum TNF-α and IL-6 concentrations and the plasma ALT and AST activities were significantly increased during reperfusion as compared with the baseline immediately before ischemia in group I/R and MB and were significantly lower in group MB than in group. I/R. The SOD activity was significantly higher while MDA content was significantly lower in group MB than in group I/R. Microscopic examination showed that liver damage was less severe in group MB than in group I/R. Conclusion The administration of MB can maintain hemodynamic stability and attenuate liver I/R injury in rabbits.