严重烧伤脓毒症病人骨骼肌蛋白降解变化及其机制探讨  

THE CHANGE OF SKELETAL MUSCLE PROTEOLYSIS IN SEVERELY BURNED PATIENTS WITH SEPSIS AND STUDY ON ITS MECHANISM

作　　者：柴家科[1] 申传安[1] 姚咏明[1] 盛志勇[1] 

机构地区：[1]解放军第304医院,北京100037

出　　处：《解放军医学杂志》2002年第9期774-776,共3页Medical Journal of Chinese People's Liberation Army

基　　金：国家自然科学基金 (编号 39970 71 6);"十五"军队医药卫生科研基金 (编号 0 1Z0 95)资助课题

摘　　要：分析严重烧伤脓毒症病人骨骼肌蛋白降解变化及其生物学机制。收集同期收治的 9例严重烧伤脓毒症病人 (烧伤脓毒症组)和 9例整形病人 (对照组 )的血、2 4h尿及股四头肌标本 ,通过放免法测定血皮质醇和TNF α的含量 ,高效液相色谱分析法检测 2 4h尿中 3 甲基组氨酸(3 MH)的排出量 ,核糖核酸印迹法和免疫组织化学法分别检测股四头肌泛素系统基因表达和蛋白表达的变化。结果发现 ,烧伤脓毒症组外周血内皮质醇和TNF α的浓度较对照组明显升高 (P <0 0 1) ;2 4h尿内 3 MH排出量明显高于对照组 (P <0 0 1) ,且3 MH排出量与外周血皮质醇和TNF α的浓度变化呈显著正相关 (r=0 93或r=0 95 ,P <0 0 1) ;股四头肌泛素mRNA 2 4kb条带和1 2kb条带的表达分别较对照组增强 5 2 %和 34% ,C2 亚基mRNA的表达较对照组增强 4 6 % ,差异有显著性意义 (P <0 0 1) ;股四头肌泛素蛋白表达较对照组增强明显 ,差异有显著意义。说明重症烧伤脓毒症病人骨骼肌蛋白降解显著增强 ,体内糖皮质激素及TNF α含量增加 ,从基因水平激活细胞内蛋白降解途径———泛素系统可能是重症烧伤脓毒症病人骨骼肌蛋白降解增强的原因之一。To study the changes of skeletal muscle proteolysis in severely burned patients with sepsis and analyze its possible mechanism, the blood, 24h urine and quadriceps femoris muscle samples were collected from nine severely burned patients with sepsis (the burn sepsis group) and nine patients with plastic operation (the control group). The plasma concentrations of cortisol and TNF α were determined with radioimmunoassay. The urinary output of 3 methylhistidine (3 MH) in 24h urine were assessed with high performance liquid chromatography. The expressions of ubiquitin mRNA and C 2 mRNA in quadriceps femoris muscle were determined by Northern blot analysis. The protein expressions of ubiquitin in quadriceps femoris muscle were determined by immunopathology. The results showed that the plasma concentrations of cortisol and TNF α in burn sepsis group were significantly higher than those of the control group ( P <0 01). The urinary output of 3 MH in burn sepsis group was significantly higher than that of the control group ( P <0 01). A positive correlation was found between the urinary output of 3 MH and the plasma concentrations of cortisol and TNF α in burn sepsis group( r =0 93 and 0 95, P <0 01), respectively. The expressions of ubiquitin mRNA 2 4 kilobase pair (kb), 1 2kb and C2 subunit mRNA in quadriceps femoris muscle of burn sepsis group were increased by 52%, 34% and 46%, respectively, as compared with those of the control group ( P <0 01). The protein expressions of ubiquitin in burn sepsis group were significantly increased in quadriceps femoris muscle of burn sepsis group than those of the control group. The results suggest that the proteolytic rate is increased during severely burned sepsis and the mechanism is related to the enhanced function of the ubiquitin system at gene and protein levels by the hypersecretion of glucocorticoid and TNF α.

关 键 词：脓毒症 烧伤 骨骼肌 蛋白降解 遍在蛋白质 基因表达 

分 类 号：R644[医药卫生—外科学]