糖调节蛋白78在脓毒症损伤心肌中表达的意义

目的研究脓毒症大鼠心脏组织内葡萄糖调节蛋白78(GRP78)的表达。方法 24只雄性SD大鼠随机分为假手术组和脓毒症(0、4、8、12、24h)组,脓毒症模型采用盲肠结扎穿孔法(CLP)。术后测血压、心率及心电图同时测定心肌酶谱,光镜观察心脏的组织形态学,实时荧光定量多聚酶链式反应(实时PCR)检测心脏组织中GRP78 mRNA的表达。结果与脓毒症0h组及假手术组相比,脓毒症大鼠的血压、心率、心电图、心肌酶谱及组织学变化均随时间延长而变化明显(P<0.05);与脓毒症0h组及假手术组相比,脓毒症组大鼠心脏组织中GRP78 mRNA明显升高(P<0.05),4h时达到了峰值,随后开始下降,到12h与24h时下降明显,但仍然高于脓毒症0h组及假手术组(P<0.05)。结论脓毒症可能通过诱导过强的内质网应激反应参与了心肌组织损伤。

Expression of Glucose-regulated Protein 78 in Myocardial Injury of Sepsis in Rats

Objective To investigate the expression of glucose regulation protein 78(GRP78) in heart tissue of the sepsis rats.Methods Twenty-four male SD rats were randomized into sham group and sepsis group(0,4,8,12,24h),in which the sepsis model adopted cecal legation perforation method(CLP).The changes of blood pressure(BP),heart rate(HR) and electrocardiogram were determined,and the concentration of myocardial enzymes(LDH,α-HBDH,CK-MB and CK) were detected.Morphological changes of hearts tissues were observed by light microscopy.The expression of GRP78 in heart tissue was detected by quantitative fluorescence polymerase chain reaction(real-time PCR).Results Compared with sham group,the BP in sepsis rats decreased significantly.Oppositely,the HR in sepsis rats increased significantly.ST depression was observed along with the significantly increase of myocardial enzyme.Importantly,it was shown that the expression of GRP78 in heart tissue of CLP rats was significantly increased(P<0.05).Conclusion The over-stress response of endoplasmic reticulum in sepsis probably results in myocardial injury.