线粒体ATP敏感钾通道在低氧预处理抗低氧性肺损伤中的作用

Role of mitochondrial ATP sensitive potassium channel in hypoxic preconditioning against hypoxic pulmonary injury

目的探索线粒体ATP敏感钾通道在低氧预处理抗低氧性肺损伤中的作用。方法利用线粒体ATP敏感钾通道阻断剂5-HD和开放剂DE采用离体肺灌流方法造成大鼠肺预缺氧/缺氧损伤模型。30只大鼠随机分成5组:对照组、缺氧组、低氧预处理(HPC)+缺氧组、Diazoxide(DE)+缺氧组、5-HD+HPC+缺氧组。通过形态学观察,灌流液总蛋白含量测定,以及肺干湿重比测定,反映各组肺受损程度。结果与单纯缺氧组相比,DE+缺氧组及HPC+缺氧组肺泡及肺组织充血水肿和红细胞渗出明显减轻,肺干/湿重比较大,灌流液蛋白含量较低(P<0.05),而5-HD+HPC+缺氧组与缺氧组无显著差异(P>0.05)。结论肺线粒体ATP敏感钾通道在低氧预处理抗低氧性肺损伤中具有保护作用。

Objective To observe the Role of Mitochondrial ATP Sensitive Potassium Channel in Hypoxic Precondition ing Against Hypoxic Pulmonary Injury. Methods Through a hypoxic preconditioning（HPC）/hypoxia injury model in an isolated lung perfusion system and by using the ATP sensitive potassium channel blocker（5-HD）and opener（DE）, Thirty rats were divided into 5 groups： control group, hypoxia group, HPC ＋ hypoxia group, DE ＋ Hypoxia group, 5-HD ＋ HPC ＋ hypoxia group. To understand various degrees of pulmonary injury respectively, the morphological change, total protein content in perfusion and dry/wet ratio of lung tissue were observed. Results Compared with the hypoxia group, the congestion and edema of lung tissue in DE ＋ hypoxia group and HPC ＋ hypoxia group is remarkably alleviated, lung dry/wet ratio is significantly increased, the protein content of the perfusion fluid is relatively less, however, the morphology of lung tissue, lung dry/wet ratio and protein content in perfusion in 5-HD ＋ HPC ＋ hypoxia group had no significant difference. Conclusion The opening of pulmonary mitochondrial ATP sensitive potassium channel might play a role in hypoxic preconditioning against hypoxic pulmonary injury.