外源性胆红素对大鼠肾缺血再灌注损伤的作用

Effect of exogenous bilirubin on ischemia reperfusion injury of rat kidney

目的探索外源性胆红素在大鼠肾缺血再灌注过程中的作用及其机制。方法60只健康雄性Wistar大鼠随机分为假手术组、IRI模型组、胆红素(BR)处理组,观察各组动物在手术及静脉注射不同剂量胆红素干预后的肾功能改变,并测定肾组织超氧化物歧化酶(SOD)、丙二醛(MDA)含量和总抗氧化能力(T-AOC),同时观察肾组织形态学改变。结果与假手术组相比,IRI模型组SOD、T-AOC含量显著降低(P<0.05),MDA显著升高(P<0.05),肾功能损伤严重。与模型组比较,2.5、5BR处理组能不同程度地增强SOD、T-AOC的活力(P<0.05),显著降低MDA含量,减轻肾功能的损伤,但10BR处理组此作用不显著。结论①外源性胆红素可能通过增强组织T-AOC和SOD活性提高大鼠肾组织的抗氧化应激的能力,减轻肾组织的炎性损伤,从而减轻大鼠肾IRI,保护肾功能;②胆红素的作用与其剂量有关,一定剂量的胆红素可以减轻大鼠肾IRI,保护肾功能。

Objective To examine the effect of exogenous of bilirabin on ischemia-reperfusion injury of rat kidney, and discuss the mechanisms of this effect. Methods Sixty healthy male Wistar rats were divided into three groups randomly： Sham operation group,Ischemia-reperfusion model group （IR group） and Bilirubin treatment group （BR group）. Sham group and IR group were treated with the same volume （1ml） vehicle as BR group, while BR group treated with the same volume （1ml） vehicle in which dissolved different dose of bilirubin. At the different time point after sham operation or reperfusion, blood samples were obtained in each group rats for measure of Cr and BUN, while the left kidneys were harvested for measurement of SOD, MDA, T-AOC and histological changes. Results Compared with the Sham operation groups： BUN and Cr of IR group increased（P〈0.05）; T-AOC, SOD of IR group decreased （P〈0.05）; Compared with the IR modle groups： T-AOC, SOD of 2.SBR and 5BR groups increased （P〈 0.05）, and MDA content decreased. But in 10BR group, there was no significant increase of T-AOC, SOD activity and derease of MDA content （P〈0.05）. Conclusion Exogenous bilirubin can attenuate ischemia-reperfusion injury and protect function of rat kidney probably through its anti-oxidation and anti-inflammatory action; At the same time, within the effective dosage range, this action is correlated with its dosage.