醋酸精氨酸对烧伤大鼠肠上皮细胞线粒体呼吸功能影响的实验研究

Effects of enteral supplementation with arginine acetate on intestinal epithelium mitochondria respiratory function in burned rats

目的研究醋酸精氨酸强化的肠内营养对烧伤大鼠肠上皮细胞线粒体呼吸功能的影响。方法采用30%体表面积Ⅲ度烧伤大鼠模型,72只大鼠随机分为伤前对照(C)组、普通肠内营养(B)组及醋酸精氨酸强化的肠内营养(Arg)组。B组和Arg组采用等氮等热卡的营养支持,Arg组大鼠每天予醋酸精氨酸1.0g/kg,B组予等量丙氨酸。观察各组大鼠肠黏膜血流量(IMBF)和一氧化氮(NO)含量变化,并对肠上皮细胞线粒体呼吸控制率(RCR)、磷氧比(P/O)及肠道氧摄取率(Oext)进行检测。结果烧伤后两组大鼠肠道IMBF、RCR、Oext显著降低,两组相比,Arg组大鼠肠黏膜NO含量以及RCR、Oext和IMBF明显高于B组。结论严重烧伤后肠道氧摄取率降低,肠上皮细胞线粒体呼吸功能受损,氧化磷酸化失偶联。Arg能增加肠黏膜NO合成,改善肠道血供,增加氧摄取率,减轻肠上皮细胞线粒体呼吸功能受抑程度。

Objective To study the effects of arginine acetate on intestinal epithelium mitochondria respiratory function in burned rats.Methods Seventy-two Wistar rats were randomly divided into three groups,i.e.normal control(C),burn control(B),and burn with arginine acetate treatment(Arg) group.Burned rats were inflicted with 30% TBSA full thickness burns.There were isonitrogenous and isocaloric intake in B and Arg group,Arg and B group rats had been given arginine acetate 1.0 g.kg-1.d-1(arginine 0.75 g.kg-1.d-1) or alanine(0.75 g.kg-1.d-1) for 7 days,respectively.The following indices including respiratory control rate(RCR),oxygen extraction(Oext),P/O ratio,intestine mucosal blood flow(IMBF) and NO contents were measured at the time table of post burn day(PBD) 1,3,5,7.Results After burn injury,the RCR,Oext,P /O ratio and IMBF were significant decreased in both B and Arg groups,but all indices were remarked increased in Arg group than those in B group.Conclusions It is suggested that mitochondria respiratory function was damaged and mitochondria oxidative phosphorylation was discoupling after burn injury.arginine acetate supplementation is beneficial to improving IMBF,increasing Oext,abating the extent of mitochondria respiration dysfunction and promoting oxidative phosphorylation.