烧伤合并内毒素血症TNFαmRNA原位表达与早期心肌损害的实验研究

An experimental study on the relationship between early myocardial injury and the in situ expression of TNFα mRNA in burned rats with endotoxemia

目的 观察TNFαmRNA及其蛋白在心肌细胞的原位表达 ,探讨烧伤合并内毒素血症早期心肌损害的可能机制。 方法 采用 2 0 %TBSAIII度烧伤复合内毒素血症多脏器损害模型 ,时相点设为伤后 0 .5、1、3、6、12、2 4和 48h。将 178只大鼠随机分为烧伤复合内毒素注射组 (烧注组 )、单纯烧伤 (单烧组 )、单纯内毒素注射组 (单注组 )和正常对照组。采用光、电镜观察 ,ELISA及免疫组化 ,原位杂交染色 ,等观察大鼠心肌形态功能变化、血清TNFα含量变化、TNFαmRNA及其蛋白在心肌细胞的定位及分布。 结果 烧注组致伤早期心肌出现一系列损害性改变 ,如波浪变性、收缩带形成、肌纤维断裂和灶性胞浆内溶解等。左室收缩压 (LVSP)及室内压最大变化速率 (±dp/dtmax)显著下降 (P <0 0 1)。血清TNFα水平于 1h明显升高 (P <0 0 1) ,3～ 6h达高峰。TNFαmRNA主要定位于心肌细胞和部分炎细胞。而单因素组病变程度轻 ,心肌损害不明显 ,血清TNFα峰值滞后以及心肌组织TNFαmRNA表达相对较弱。 结论 烧伤合并内毒素血症状态下 ,心肌本身可表达TNFαmRNA及其蛋白 ,并可能作为机体TNFα产生来源之一 。

Objective To observe the in situ expression of TNF mRNA and protein in myocardial cell,so as to explore the possible mechanism of early myocardial injury in scalded rats with endotoxemia. Methods One hundred and seventy eight Wistar rats inflicted with 20%TBSA Ⅲdegree napalm burn compound with endotoxemia and multiple organ injury were employed as the model and were randomly divided into four groups as follow.(1) burn and infusion group(BI):the rats were burned and infused with endotoxin.(2)simple b...