Effects of remifentanil pretreatment on MDA,SOD and NO in rabbits' lung tissue during acute hemorrhagic shock

Objective To observe the effects of remifentanil pretreatment on MDA,SOD and NO in rabbits' lung tissue during acute hemorrhagic shock.Methods 40 healthy rabbits were randomly divided into three groups: Low-dose remifentanil group(R1 group,n= 16) that remifentanil 0.66μg/kg/min was pumped 15 minutes before bleeding.According to shock time R1 group was divided into one-hour group(RO1,n=8) and two-hour group(RT1,n=8);High-dose remifentanil group(R2 group,n=16) R2 group remifentanil 1.32μg/kg/min was pumped 15 minutes before bleeding.According to shock time R2 group was divided into one-hour group(RO2,n=8) and two-hour group(RT2,n=8);Control group NS(group C,n=8).NS continued to pump into same volume of normal saline.The model of acute hemorrhagic shock was established by modified Wigger's methods.After experiment,lung tissue wet-weight /dry-weight ratio(W/D),myeloperoxidase(MPO) activity,malondialdehyde(MDA) and the changes of circulating nitric oxide(NO) was measured.Results In group R1 and R2 the W/D lower than group C;in group R1 and R2 the activity of SOD and NO was higher than before,while MDA was abated(P0.05).To compare with RO2 group,content of MDA were significantly higher,and the activity of SOD decreased in group RO1,RT1 and RT2.Conclusion Remifentanil pretreatment may decrease MDA content,increase SOD and NO activity in rabbits lung tissue during the accurate hemorrhagic shock.