C5aR和P38-MAPK在脓毒性休克大鼠心肌损伤中的作用

The role of C5aR and P38-MAPK in the rats model of septic shock with myocardial injury

目的 研究补体C5a受体与P38-MAPK在脓毒性休克情况下诱导心肌损伤的关系.方法 采用盲肠结扎剪切法构建早期脓毒性休克大鼠动物模型,实验地点在武汉大学人民医院麻醉科实验室.30只Sprague-Dawley大鼠随机（随机数字法）分为正常对照组6只和模型组24只（12 h组12只,24 h组12只）.12 h组于术后12 h时点检测血清乳酸脱氢酶（LDH）和肌酸激酶（CK）水平,12 h后麻醉处死大鼠,迅速开胸取出心脏组织,行HE染色、应用免疫组织化学方法检测C5a受体和P38-MAPK的表达情况.24 h组亦于术后24 h时点检测血清LDH和CK值,24 h后处死大鼠取心肌组织行HE染色、检测C5a受体和P38-MAPK的表达情况.结果 模型组（12 h组和24 h组）与正常对照组相比,LDH值和CK值均明显升高（P＜0.05）.24 h组LDH值和CK值与12 h时间点相比,差异具有统计学意义[（2 568.9±280）vs.（2 201.2±149）,（5 029.7±458）vs.（2 629.4±140）,P＜0.05].C5aR和P38-MAPK灰度值分析显示,模型组与正常对照组相比,均有显著性增高（P＜0.05）,24 h组较12 h组相比,差异具有统计学意义[（702.77±122）vs.（388.36±113）,（646.40±181）vs.（307.32±61）,P＜0.05].相关分析显示C5aR和P38-MAPK存在显著正相关关系,（P＜0.05）,P38-MAPK与LDH和CK均存在显著正相关关系（P＜0.05）.结论 C5a受体和P38-MAPK在诱导脓毒性休克心肌损伤中有着强大的协同效应.

Objective To investigate effects of complement C5a receptor and P38-MAPK on myocardial injury brought about by septic shock in rats. Method The early septic shock models were established by the method of cecal ligature and incision （CLI）. A total of 30 Sprague-Dawley rats were randomly（ random number） divided into normal control group （ n = 6 ） and model group （ n = 24 ） and the model group was further 12 hours later divided into 12 h subgroup （n = 12） and 24 h subgroup （n = 12）. The arterial blood samples were collected 12 hours later for detecting the levels of lactate dehydrogenase （LDH） and creatine kinase （CK）, and then the rats were sacrificed and the myocardial tissues were taken to assay the expressions of C5a receptor and P38-MAPK by using immunohistochemistry after HE staining. And the above procedure as did in 12 h subgroup was done 24 hours later. Results Compared with the control group, the levels of LDH and CK in rats of Model group were significantly higher （P 〈 0. 05）. There were significant differences in LDH and CK between 24 h subgroup and 12 h subgroup [（2 568.9 ± 280） vs. （2 201.2 ± 149）] and [（5 029.7±458） vs. （2 629.4±140）] ,P〈0. 05, P〈0.05. The analysis of C5aR and P38-MAPK gray values showed that there were significant differences between the model group and normal control group [（702.77 ±122） vs. （388.36±113）], P〈0. 05 and [（646.40±181） vs. （307.32 ±61）] ,P〈0.05,and those differences also found between the 24 h subgroup and 12 h subgroup. There was a significant positive correlation between C5aR and P38-MAPK （P〈0.05 ）, and also the P38-MAPK had significant positive relationships with LDH（P〈0.05） and CK （P〈0.05）. Conclusions The C5aR strongly potentiates the P38-MAPK to induce myocardial injury by septic shock.