体外循环对中性粒细胞膜结合弹性蛋白酶的影响

时间:2020-10-06 19:27:49 药学毕业论文 我要投稿

体外循环对中性粒细胞膜结合弹性蛋白酶的影响

作者:王维俊,汤敏,Y.John Gu,陈长志
【关键词】 体外循环
  【摘要】 目的 探索体外循环前后膜结合弹性蛋白酶(MBE)动力学变化,及MBE与术后炎性反应及组织功能之间可能存在的联系。方法 连续收集10例体外循环下冠状动脉搭桥手术病人的资料,血样采集时间为开胸前、主动脉开放后、体外循环结束时、停机后3h和6h、术后第一天。分离血样中的中性粒细胞,使用底物分析法测定被分离的中性粒细胞的MBE。通过常规实验方法测定炎性反应和组织功能的生化标记物。结果 开放主动脉后,MBE轻度升高,停机时达峰值,在术后第一天恢复到术前水平。与主动脉开放后中性粒细胞在肺内滞留相比,左房与右房血中的MBE没有差异。MBE或MBE总活性与术后炎性反应标记物如C反应蛋白(CRP)及组织功能标记物如乳酸、肌酸磷酸激酶(CPK)、丙氨酸氨基转移酶之间均无相关关系。结论 体外循环促使中性粒细胞MBE表达,并在停机时达高峰,但与体外循环后炎性反应和组织功能的生化标记物之间没有特定关联,提示体外循环中还有其他重要机制参与了术后炎性反应和器官功能障碍的发生。

  【关键词】 体外循环;中性粒细胞膜结合弹性蛋白酶

  Effect of CPB on membrane-bound elastase of neutrophils
  【Abstract】 Objective To study the effect of cardiopulmonary bypass (CPB) on the kinetic change of membrane-bound elastase (MBE) and its possible link to the postoperative inflammation and organ function.Methods Ten consecutive patients undergone elective coronary bypass surgery with CPB were recruited in the study.Blood samples were taken before median sternotomy,after aortic declmping,at the end of CPB,3h and 6h after CPB and on the first postoperative day respectively.MBE was determined by substrate assay from isolated neutrophils.Inflammation and organ function markers were determined with routine laboratory methods.Results MBE slightly increased after aortic declamping,reached to its peak at the end of CPB,and returned to its preoperative level on the first postoperative day.In contrast to lung sequestration of neutrophil count,there were no transpulmonary gradient of MBE between left and right atrium after aortic declamping.Neither MBE nor total MBE activity was positively correlated with the postoperative inflammation markers such as blood lactate and C-reactive protein and organ function markers such as creatine phosphokinase and alanine aminotransferase.Conclusion CPB induces MBE expression on neutrophils with its peak at the end of CPB.Lack of association between neutrophil MBE and clinical markers suggests that multiple systems are involved in the post-CPB inflammatory response and organ dysfunction.
  【Key words】 cardiopulmonary bypass;membrane-bound elastase of neutrophils
  体外循环(CPB)能通过激活循环中细胞与体液成分,引起全身炎性反应综合征[1,2]。激活的'中性粒细胞释放出的弹性蛋白酶,被认为是能够降解各种蛋白如弹性蛋白、纤维蛋白、糖蛋白等强有力的蛋白水解酶之一[3]。心内直视手术的病人在转流中和转流后,中性粒细胞均能释放弹性蛋白酶[4~7],但游离弹性蛋白酶能被体内广泛存在的蛋白水解酶抑制剂(protease inhibitor,PI)迅速结合而失去活性[8]。最近发现,中性粒细胞膜结合弹性蛋白酶(membrane bound elastase,MBE)能抵抗血浆和组织中蛋白水解酶抑制因子的作用[9],而且结合于中性粒细胞膜上的弹性蛋白酶,在攻击血管内皮细胞和引起组织损伤方面,较血浆中游离的弹性蛋白酶具有更强的生物活性[10~12]。本研究的目的就是研究心脏手术病人在转流中和转流后MBE的动力学变化,并试图寻找其与术后炎性反应及组织功能变化之间的关系。