模拟深埋条件下挤压伤复合低氧缺水缺食大鼠解除挤压后肝脏功能和病理损伤特点

Functional and pathological changes of rat liver after release from crush combined with hypoxia and deprivation of food and water under simulated deep burial

目的研究模拟深埋条件下挤压伤复合低氧缺水缺食3 d大鼠解除挤压（即模拟＂黄金抢救时间72 h＂）后即刻至28 d肝脏功能和结构的恢复规律与特点。方法应用雄性Wistar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]。各时间点每组6只,于解除挤压后即刻、1、3、7、14、28 d检测血清丙氨酸氨基转移酶（ALT）含量;切取肝脏,常规制片,光镜和电镜观察。结果①复合组1只大鼠于解除挤压后0.6 d猝死,其他3组未发生死亡。②复合组和单挤组ALT值于解除挤压后即刻明显升高,尤以复合组最显著（P〈0.01）,3 d后均恢复正常。③复合组和单挤组肝质量均明显减轻,尤以复合组最显著（P〈0.05）。④复合组解除挤压后即刻和1 d肝索萎缩,肝细胞变性、凋亡,糖原减少,线粒体空化,并累及枯否细胞、储脂细胞、内皮细胞;3-7 d渐减轻,14-28 d未完全恢复。单挤组较之轻微。结论挤压伤大鼠在解除挤压后即刻肝脏功能和结构发生明显损伤,3~28 d渐恢复,具有病变累及全肝性、自行恢复性、功能与结构恢复不同步性和恢复程度差异性特点。

Objective To study the function and pathological changes of rat liver combined with hypoxia and deprivation of food and water for 3 days（＂ golden rescue time 72 h＂）under simulated 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].Alanineaminotransferase（ALT） contents of serum were measured at 0,1,3,7,14 and 28 d after release from extrusion,and six animals for each group at every time.After histological section,the livers were observed by optical and electronic microscopy.Results ① In the combined group,one rat died at 0.6 d after release from extrusion.No death was seen in other three groups.② ALT values of combined group and crush group increased immediately release from extrusion,especially for the combined group（P〈0.01）,and 3 days later both restored to normal.③The liver weight of combined group and crush group both reduced significantly,especially for the combined group（P〈0.05）.④Liver atrophy,degeneration and apoptosis of liver cells,glycogen decrease and mitochondria cavitation was observed in combined group immediately and 1 d after release from extrusion,which involving kupffer cells,fat storing cells and endothelial cells.Above changes were alleviated gradually during 3- 7 d,but not fully recovered during 14- 28 d and mitigated in crush injury group.Conclusion Obvious functional and structural injury of rat liver was caused immediately after release from extrusion,which was alleviated gradually during 3- 28 d,and characterized as whole liver involved,restorative,different recover step and degree of function and structure.