模拟深埋条件下持续性挤压伤复合低氧缺水缺食诱导肝细胞凋亡及其机制研究

Research on the regulation and mechanism of apoptosis of liver cells when sustained crush injury combined with hypoxia and deprivation of food and water under simulated deep burial in rats

目的研究模拟深埋条件下持续性挤压伤复合低氧缺水缺食大鼠的肝细胞凋亡规律及其机制。方法Wistar雄性大鼠144只,随机分为对照组、单纯挤压组（单挤组）、低氧缺水缺食组（三缺组）、挤压伤复合低氧缺水缺食组（复合组）,采用钳夹双后肢近端方法建立挤压伤模型[压力为（44.1±2.9）N],于致伤后1、3、5 d活杀取材,各时间点每组6只,常规制片,采用原位末端标记法（TUNEL）检测肝细胞凋亡,免疫组化链霉菌抗生物素蛋白-过氧化物酶连结法（SP）对肝脏组织中凋亡相关因子Bax、Bcl-2进行平均光密度（MOD）定量检测。结果①凋亡指数：与正常对照组比较,单挤组、三缺组和复合组肝细胞凋亡指数于1-5 d呈现逐步增高趋势,差异具有统计学意义（P〈0.05,P〈0.01）,其中复合组尤为明显。②凋亡相关因子Bax表达逐渐增强,MOD值逐渐增高,单挤组、三缺组和复合组于1-5 d均显著高于对照组（P〈0.05,P〈0.01）;Bcl-2表达呈进行性减弱,MOD值进行性下降,与对照组比较,其中单挤组和三缺组在3 d和5 d差异具有统计学意义（P〈0.05,P〈0.01）,复合三缺组下降最明显,于1-5 d差异均有统计学意义（P〈0.05,P〈0.01）,并依次显著低于前两组。结论无论挤压或三缺均会导致大鼠肝细胞凋亡指数增加,复合组尤为明显,具有高发性、速发性、进行性、累及细胞多样性特点;Bax和Bcl-2参与肝损伤过程。

Objective To study the tolerance of life and liver function and pathological changes of rats subjected to continuous crush injury combined with hypoxia and deprivation of water and food under the simulant condition of deep burial.Methods 144 male Wistar rats were randomly divided into four groups：control group,crush group,hypoxia combined with deprivation of water and food group（three-lack group）,and crush injury combined with hypoxia and deprivation of water and food group（combined group）.Crush injury model was established by clamping the near ends of double hind limbs [pressure for（44.1 ± 2.9） N].The experiment data was recorded at 1,3,5 d after injury,and six animals for each group at every time.After histological section,quantitative molecular pathological methods were used to detect apoptosis index of myocardial cells and expression of apoptosis factors（Bax,Bcl-2）.Results ① The apoptosis index：crush group,three-lack group and combined group compared with control group,liver cell apoptosis index in 1- 5 d showed a trend of increased gradually,the differences were statistically significant（P〈0.05,P〈0.01）,particularly combined group.②expression of apoptosis factors：increased Bax expression,MOD increased gradually,crush group,three-lack group and combined group in 1- 5 d were significantly higher than that of control group（P〈0.05,P〈0.01）;The Bcl-2 expression in progressive weakening,MOD progressive decline,compared with control group,including crush group and three-lack group in 3 d and 5 d statistically difference（P〈0.05,P〈0.01）,combined group fell the most obvious deficiency,in 1- 5 d were statistically significant（P〈0.05,P〈0.01）,and significantly lower than the former two groups.Conclusion Whether it was the crush or three-lacks,can cause rat hepatocyte apoptosis index increased,particularly combined group was the most obvious,this has a high incidence of sexual diversity,fast onset,progressive,involving cell characteristic;Bax and Bcl-2 involved in liver injury process.