胰岛素对烫伤大鼠肝脏氧自由基损伤的保护作用

Protective effect of insulin on oxygen-radical induced hepatic injury in severely scalded rats

目的了解大鼠严重烫伤后早期应用胰岛素对肝脏氧自由基损伤的保护作用。方法雄性SD大鼠84只,随机分为正常组、盐水组、胰岛素组,每组各28只。后2组大鼠在背部造成30%TBSAⅢ度烫伤,伤后立即腹腔注射等渗盐水40ml/kg或皮下注射胰岛素3U/kg。伤后6、12、24、48h,检测盐水组和胰岛素组大鼠肝脏总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)、活性氧(ROS)及血清丙氨酸转氨酶(ALT)含量,同时检测肝脏胞间黏附分子1(ICAM-1),光学显微镜下观察肝细胞形态学改变。正常组大鼠亦作相应检测。结果与正常组比较,盐水组大鼠伤后6h肝脏T-AOC、SOD明显降低,ROS明显升高(P<0.05或P<0.01);伤后12～48h血清ALT及ICAM-1均高于正常组(P<0.01)。伤后24h,胰岛素组大鼠肝脏T-AOC、SOD分别为(386±75)、(210±39) U/g,较盐水组(124±18)、(111±9)U/g明显升高(P<0.01);ROS为(154±29)U/g,较盐水组(351±41)U/g明显降低(P<0.01)。伤后48h,胰岛素组大鼠血清ALT及肝脏ICAM-1与盐水组比较呈下降趋势(P<0.01)。组织病理学结果显示,胰岛素可减轻烫伤后肝细胞损伤程度。结论严重烫伤后早期用胰岛素干预,可增强大鼠肝脏抗氧化损伤能力,对肝脏有保护作用。

Objective To investigate the protective effect of insulin on oxygen-radical induced hepatic injury in severely scalded rats in early stage of severe scald. Methods Eighty-four male Sprague-Dawley rats were randomly divided into three groups： i. e, normal group, saline group, and insulin group, with 28 rat in each group. The rats in the latter two groups were subjected to 30% TBSA full-thickness scald on the back, and received intra-peritoneal injection of 40ml/kg isotonic saline, and subcutaneous injection of 3 IU/ kg insulin, respectively. The total anti-oxygen capability （T-AOC）, the expression of superoxide dismutase （SOD）, reactive oxygen species （ROS） and intercellular adhesion molecule （ICAM-1） in hepatic tissue, and serum alanine transaminase （ALT） were determined in each group at 6, 12, 24, 48 post-scald hours （PSH） with corresponding methods. Results The hepatic T-AOC and SOD content were obviously decreased, while the ROS content were markedly increased at 6 PSH in saline group compared with that in normal group （ P 〈0.05 orP 〈 0.01 ）. The expression of ICAM-1 and serum content of ALT were significantly higher than that in normal group at 12PSH and 48 PSH （ P 〈 0.01 ）. At 24 PSH, the hepatic T-AOC （386 ±75 ）U/g and SOD content （210 ± 39 ）U/g were obviously higher in insulin group than those in saline group [ （124 ±18） , （111 ±9）U/g, respectively, P 〈 0.01） , but the ROS content （154 ~29 ） U/g was much lower than that in saline group [ （351 ±41 ）U/g, respectively, P 〈 0.01 ]. At 48 PSH, the serum content of ALT and hepatic expression of ICAM-1 in insulin group exhibited obvious difference when compared with those in saline group （ P 〈 0.01 ）. Meanwhile, Pathological examination showed that hepatic injury was alleviated by insulin administration after scald. Conclusion Insulin administration early after severe scald exhibits protective effect on liver function by improving anti-oxygen radical ability of rat liver.