摘要
目的 :研究脓毒症时不同类型骨骼肌蛋白降解率的变化 ,分析其可能的机制。方法 :大鼠腹腔注射内毒素制成脓毒症模型 ,随机分成内毒素攻击后 2、6、12和 2 4小时组 ,每组设正常对照 ;利用骨骼肌充分氧供离体孵育系统 ,采用氨基酸全谱分析仪测定脓毒症大鼠伸趾长肌 (EDL )和比目鱼肌 (SOL )蛋白降解率。用放射免疫分析 (RIA)方法测定大鼠血浆中糖皮质激素含量。结果 :内毒素攻击后大鼠 EDL总蛋白降解率和肌纤维蛋白降解率在 2和 6小时较正常对照组明显增加 ,肌纤维蛋白降解率增加 1～ 2倍 ,6小时达峰值 ,12和 2 4小时均无明显变化。大鼠 SOL 总蛋白降解率和肌纤维蛋白降解率在内毒素攻击后均未见显著变化。内毒素攻击后不同时间点血浆糖皮质激素含量较正常对照组均显著增加 (P均 <0 .0 1)。EDL 肌纤维蛋白降解率与血浆糖皮质激素含量呈显著正相关 (r=0 .982 8,P<0 .0 1)。结论 :不同类型骨骼肌对脓毒症刺激的反应不同 ,快白肌纤维对脓毒症刺激比慢红肌纤维敏感 ;血浆中糖皮质激素浓度增加是导致脓毒症骨骼肌蛋白降解增强的重要因素之一。
Objective:To study the changes in proteolytic rate of different kinds of skeletal muscle in rats with sepsis,and analyze its possible mechanism.Methods:The rats with sepsis was established by administering endotoxin into the peritoneal cavity.The rats were randomly divided into 4 groups as follows:2,6,12 and 24 hours after administration of endotoxin,each group included normal control.We use the in vitro muscle incubation system with sufficient oxygen supply as well as amino acid automatic analyzer for detection of the proteolytic rate of extensor digitorium longus(EDL) and soleus(SOL)muscle.The level of serum glucocorticoid was determined by radioimmunoassay.Results:Total proteolytic rate in EDL muscle increased slightly at 2 hours and 6 hours after administering endotoxin,no statistically significant difference was observed at 12 hours and 24 hours.There was a 12fold increase in the myofibrillar proteolytic rate at 2 hours and 6 hours,40% increase at 12 hours.There was no statistically significant difference in total and myofibrillar proteolytic rate in SOL muscle throughout the course of observation period.Plasma concentration of glucocorticoid notably increased of each observation time point compared with normal control(all P<0.01).There was a positive correlation between the plasma concentration of glucocorticoid and the myofibrillar proteolytic rate of skeletal muscle (r= 0.982 8,P<0.01).Conclusions:The fastwhite muscle is more sensitive to sepsis than that of slowred muscle.Glucocorticoid is probably the important mediator of skeletal muscle proteolysis.
出处
《中国危重病急救医学》
CAS
CSCD
2001年第5期272-274,共3页
Chinese Critical Care Medicine
基金
国家自然科学基金资助项目! (No.3 9970 716)
军队医药卫生科研基金资助项目! (No.98M15 5 )
