血浆中组织蛋白酶L在大鼠急性心肌缺血及缺血再灌注后的表达

目的 检验大鼠心肌缺血及缺血再灌注后组织蛋白酶L在血浆中的表达,探讨其能否作为心肌缺血标记物.方法 建立大鼠急性心肌缺血模型（心肌缺血30 min、1h、2h组）、缺血再灌注模型（缺血再灌注组）以及异氟烷预处理后的缺血再灌注模型（异氟烷预处理组）.同时设有正常对照组、假手术组以作对照.用ELISA法检验血浆中组织蛋白酶L的含量,同时用TTC染色测量心肌梗死面积. 结果 大鼠急性心肌缺血后,各组血浆中的组织蛋白酶L含量与正常对照组、假手术组相比,差异无统计学意义（P＞0.05）.缺血再灌注组,血浆中组织蛋白酶L的表达增多到正常对照组2.37倍（P＜0.05）.异氟烷预处理组血浆组织蛋白酶L和心肌梗死面积都较缺血再灌注组降低（P＜0.05）.结论 血浆中组织蛋白酶L不适合作为单纯急性心肌缺血的早期血浆标记物,异氟烷预处理可以降低缺血再灌注造成的血浆组织蛋白酶L高表达.

Cathepsin L Expression in Plasma after Acute Myocardial Ischemia and Ischemia-reperfusion in Rats

Objective To test cathepsin L as a biomarker of myocardial ischemia by examination ofcathepsin L expression in plasma after myocardial ischemia and ischemia-reperfusion in rats. MethodsThe rat models were established and divided in acute myocardial ischemia model （myocardial ischemia30min, 1 h, 2 h groups）, ischemia-reperfusion model （ischemia-reperfusion group）, and isoflurane-pretreat-ed ischemia-reperfusion model （isoflurane-pretreated group）, respectively. Normal control group and sham-op-erated group were established as contrast. The contents of cathepsin L in plasma were examined by ELISAand myocardial infarction areas were measured after TTC staining. Results No statistical significantchanges were found among the experimental groups compared with the normal control group and sham-operated group （P〉0.05）. The cathepsin L from the ischemia-reperfusion group increased to 2.37 timescompared with the normal control group （P〈0.05）. The cathepsin L and myocardium infarction size ofisoflurane-pretreated group decreased compared with the ischemia-reperfusion group （P〈0.05）. Conclu-sion The cathepsin L in plasma is not a promising biomarker of acute myocardial ischemia. Isofluranepreconditioning can reduce the cathepsin L in plasma caused by ischemia-reperfusion injury.