机械创伤通过增加活性氧和NO导致心肌细胞凋亡

Mechanical trauma caused cardiomyocyte apoptosis by increasing the levels of reactive oxygen and nitric oxide

目的观察机械创伤后活性氧和一氧化氮(NO)水平的变化规律,并探讨其在创伤致心肌细胞凋亡中的作用。方法使用Noble-Collip创伤仪制备大鼠机械创伤模型。创伤后0,3,6,12,24 h检测各指标。同时在创伤后随即给予FeTMPyP,按照2 mg/kg剂量腹腔注射,溶剂对照组给予等量生理盐水,创伤后12 h比较各指标。采用光泽精加强发光法测定心肌组织超氧阴离子的含量,应用化学发光法检测心肌组织NO的含量,通过ELISA方法测定心肌组织硝基酪氨酸(NT)含量,使用TUNEL和caspase-3活性测定两种方法观察心肌细胞凋亡情况。结果机械创伤后心肌细胞凋亡显著增高(P<0.01),心肌组织超氧阴离子水平和NO含量显著升高(P<0.01),且二者结合的产物过氧亚硝基(ONOO-)也明显增加(P<0.01);给予ONOO-清除剂可显著降低心肌组织NT水平(P<0.01),且显著降低心肌细胞凋亡(P<0.01)。结论机械创伤通过使活性氧和NO水平增加而导致心肌细胞凋亡。

Objective To observe the variation of reactive oxygen and nitric oxide levels after mechanical trauma,and to explore its role in the mechanical trauma-induced cardiomyocyte apoptosis.Methods Mechanical trauma rat model was established by Noble-Collip drum.Myocardial superoxide content was determined by lucigenin-enhanced luminescence.Nitric oxide（NO） content in myocardial tissue was detected by chemiluminescene method.Myocardial nitrotyrosine（NT） content was measured by ELISA.Cardiomyocyte apoptosis was confirmed by TUNEL and caspase-3 activity detection.All indices were detected at 0,3,6,12,24 h.FeTMPyP was given immediately after trauma,and the indices were detected and compared at 12 h.Results Cardiomyocyte apoptosis was increased after mechanical trauma（P0.01）.Myocardial superoxide and NO content significantly increased after mechanical trauma（P0.01）.Peroxynitrite（ONOO-）,the product of superoxide and NO,was elevated significantly in myocardial tissue after mechanical trauma（P0.01）.Myocardial NT content and cardiomyocyte apoptosis remarkbly decreased after ONOO-scavengers treatment（P0.01）.Conclusion Mechanical trauma could cause the cardiomyocyte apoptosis by increasing the levels of reactive oxygen and nitric oxide in myocardial tissues.