Effects of intravenous remifentanil infusion on myocardial oxidative stress in rats / 中华麻醉学杂志

ABSTRACT

ObjectiveTo investigate the effects of intravenous (iv) remifentanil infusion on myocardial oxidative stress in rats.MethodsOne hundred and eighty male SD rats weighing 250-300 g were randomly divided into 15 groups (n =12 each)group control (group C); group ischemic preconditioning (group IPC); group remifentanil preconditioning ( group RPC ) ; while ia iv remifentanil infusion groups,iv remifentanil was infused at 4 different rates ( 1,5,10,20μg· kg- 1 · min- 1 ) and each rate was maintained for 15,60 and 120 min respectively.Myocardial ischemia was induced by occlusion of left coronary artery anterior descending branch for 30 min followed by 120 min reperfusion in 6 rats in each group.In group IPC myocardial ischemia was preceded by 3 cycles of 5min ischemia-5min reperfusion;whilein group RPC3cycles of 5min remifentanil infusion at 5 μg· kg-1 · min-1 were applied at 5 min interval before ischemia.Six rats in which I/R was produced were sacrificed in each group,myocardial infarct size (IS) and the area at risk (AAR) were measured and IS/AAR was calculated.The left 6 rats in each group were sacrificed at the corresponding time point (the end of each treatment)and superoxide radical expression and MDA and nitrotyrosine contents in myocardium were determined.Results IS/AAR was significantly decreased in groups IPC,RPC,1 μg·kg-1 ·min-1 × 120 min,5 μg·kg-1 ·min-1 × 60or 120 min and 10 μg· kg- 1 · min- 1 × 60 min as compared with group C.Compared with group C,the myocardial superoxide radical expression was significantly up-regulated in groups 1 μg· kg-1· min-1 × 120 min, 5 μg·kg-1 ·min-1 ×60 or 120 min,10μg·kg-1 ·min-1 ×60 or 120 min and 20 μg·kg-1 ·min-1 × 15,60 or 120min,and myocardial MDA and nitrotyrosine contents were significantly increased in group 20 μg· kg-1 · min-1 ×15,60 or 120 min.ConclusionLonger duration of high rate remifentanil infusion can induce myocardial oxidative stress in rats.