阿米洛利对大鼠肺缺血再灌注损伤的保护作用

The protective effects of amiloride against lung ischemia-reperfusion injury in rats

目的观察阿米洛利对大鼠肺缺血再灌注损伤(LIRI)的保护作用及其可能机制。方法建立大鼠在体肺缺血再灌注模型。将雄性Wistar大鼠54只随机分为手术对照组(C组)、缺血再灌注组(IR组)、阿米洛利组(A组)。每组分别在缺血45min,再灌注60、120min3个时点处死6只大鼠,留取血浆和右肺组织,测定肺组织湿干质量比值(W/D)、髓过氧化物酶(MPO)活性,肺组织中细胞凋亡指数(AI)及血清丙二醛(MDA)含量,并进行肺组织病理学检查。结果再灌注期间IR组肺组织W/D、MPO活性、AI、血清MDA均升高,而预先给予阿米洛利干预后可以减弱缺血再灌注诱导上述指标的升高。肺组织病理学检查显示阿米洛利预先给药减轻肺缺血再灌注损伤。结论阿米洛利对肺缺血再灌注损伤有保护作用,可能与其抑制氧自由基生成、中性粒细胞浸润及细胞凋亡有关。

Objective To investigate the protective effects of amiloride on lung ischemiareperfusion injury in rats and its possible mechanisms. Methods Fifty-four healthy male Wistar rats were randomly divided into three groups： surgical controls （C group）, ischemia- reperfusion gToup （IR group） and amiloride-pretreated group （A group）. At each of three time spots （45 min iscbemia, 60 min and 120 min reperfusion）, every 6 rats from the groups were sacrifieed, collected for plasma sample and the whole right lung. The plasma contents of malondialdehyde （MDA）, the wet/ dry （W/D） weight ratio of the lung, the activity of myeloperoxidase, and apoptotic index （AI） in lung tissue were determined. Histopathologlcal study of the lung tissue was also performed. Results The plasma contents of MDA, the W/D weight ratio, MPO activity and AI in lung tissue were all significantly increased during reperfusion in IR group but considerably attenuated with Amiloride pretreatment. Pathological examination showed that the IR induced injury was also ameliorated by amiloride pretreament. Conclusion Amiloride treatment before ischemia appeared to protect the lungs against IR induced injury, possibly by inhibited PMN infiltration, reduced production of oxygen radicals and sup- pressed apoptosis of lung tissue.