磷酸肌酸预处理对大鼠肾缺血-再灌注所致肺损伤的影响

摘要

目的 探讨磷酸肌酸预处理对大鼠肾缺血-再灌注所致肺损伤的影响.方法 SPF级雄性SD大鼠45只, 8～10周龄, 体重180～220g, 采用随机数字表法, 将其分为三组:假手术组 (S组) 、肾脏缺血-再灌注组 (IR组) 和磷酸肌酸预处理组 (PCr组), 每组15只.S组仅游离肾蒂并行右肾切除术.IR组和PCr组在S组基础上制备肾缺血-再灌注模型.PCr组于缺血前30min尾静脉注射磷酸肌酸钠150mg/kg, IR组于同时点注射等容量生理盐水.再灌注6h后于同时段经左心室采集动脉血样, 血气分析记录PaO2, 检测血清丙二醛 (MDA) 浓度和超氧化物歧化酶 (SOD) 活性.Fluo-3AM染色经流式细胞仪检测肺泡巨噬细胞内Ca2+浓度.取肺组织, HE染色, 光学显微镜下观察肺组织病理结果, 测定肺组织湿重/干重 (W/D) 比值.膜联蛋白V/碘化丙锭 (Annexin V/PI) 双染经流式细胞仪检测肺组织细胞凋亡比例.结果与S组比较, IR组和PCr组PaO2明显降低, MDA浓度明显升高, SOD活性明显减弱, 肺泡巨噬细胞Ca2+浓度明显升高, 肺W/D比明显增大, 肺组织病理学损伤程度明显加重, 肺组织细胞凋亡率明显升高 (P<0.05) .与IR组比较, PCr组PaO2明显升高, MDA浓度明显降低, SOD活性明显增强, 肺泡巨噬细胞Ca2+浓度明显降低, 肺W/D比明显减小, 肺组织病理学损伤程度明显减轻, 肺组织细胞凋亡率明显降低 (P<0.05) .结论 磷酸肌酸预处理可有效减轻大鼠肾缺血-再灌注诱发的肺损伤, 其机制可能与抑制氧化应激, 降低细胞凋亡及钙离子超载有关.%Objective To investigate the effects of phosphcreatine preconditioning on lung injury induced by renal ischemia-reperfusion (IR) in rats.Methods Forty-five SPF male Sprague-Dawley rats, aged 8-10 weeks, weighing 180-220 g, were randomly divided into 3 groups using a random number table:sham operation group (group S), renal IR group (group IR), and phosphcreatine preconditioning group (group PCr), 15 cases in each group.The rats in group S recieved dissoci ation of renal pedicles and right nephrectomy, on top of which renal IR model was prepared in group IR and group PCr.phosphcreatine 150 mg/kg was injected in group PCr for 30 minutes before ischemia, where as rats in group S and group I/R recieved the normal saline at the same time.The blood samples were obtained from left ventricle at 6 hours after reperfusion, the arterial blood gas analysis was performed in order to determined the oxygen partial pressure (PaO2).Serum levels of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) were also determined.Fluo 3-AM staining and flow cytometry were used to measure the concentration of alveolar macrophage calcium ions.The lung tissue was obtained with HE staining for determination of microscope examination of pathologic changes, and weight/dry (W/D) ratio were also determined.The lung tissue cell apoptotic rate was measured by Annexin V/PI apoptosis detection reagent staining and flow cytometry.Fluo 3-AM staining and flow cytometry were used to measure the concentration of alveolar macrophage calcium ions.Results Compared with group S, the histopathological demages, W/D ratio, lung tissue cell apoptotic rate, the serum levels of MDA and the concentration of alveolar macrophage calcium ions were signifcant increased (P<0.05), whereas the PaO2 and the activity of SOD were signifcantly decreased in group IR and group PCr (P<0.05).Compared with group IR, the histopathological demages, W/D ratio, lung tissue cell apoptotic rate, the serum levels of MDA and the concentration of alveolar macrophage calcium ions were signifcant decreased (P<0.05), whereas the PaO2 and the activity of SOD were signifcantly increased in group PCr (P<0.05).Conclusion Phosphcreatine preconditioning can attenuate lung injury induced by renal I/R, the mechanism is related to inhabit oxidative stress, and reduce cell apopotosis and calcium overload.