乳酸和低剂量依达拉奉联合药物后适应通过线粒体途径减轻大鼠心肌缺血再灌注损伤  

Pharmacological postconditioning with lactic acid and low dose edaravone could attenuate myocardialreperfusion injury through mitochondrial pathway

作　　者：张国明[1] 王禹[3] 李晓燕[1] 许琳[1] 孙媛媛[2] 李玉珍 刘丽凤[3] 

机构地区：[1]济南军区总医院心内科,250031 [2]济南军区总医院超声科,250031 [3]解放军总医院老年心血管病研究所 [4]基础所病理生理学教研室

出　　处：《中华心血管病杂志》2013年第8期647-653,共7页Chinese Journal of Cardiology

基　　金：国家自然科学基金资助项目（30740080）;济南军区总医院院长青年基金资助项目（201lQ08）

摘　　要：目的探讨乳酸和低剂量依达拉奉能否模拟机械后适应发挥有效的心肌保护作用。方法108只雄性SD大鼠随机分为假手术组、缺血再灌注组（I／R组）、后适应组（IP组）、乳酸组（乳酸60μl，Lac组）、低剂量依达拉奉组（依达拉奉3μg／kg，Eda组）和乳酸＋低剂量依达拉奉组（乳酸60μl＋依达拉奉3μ/kg，Lac＋Eda组）6组，每组18只。首先建立急性心肌梗死再灌注模型，然后于再灌注即刻根据分组分别进行干预，在梗死边缘分别注射不同药物或生理盐水。测定再灌注10min后右心房血浆pH值，于不同时间点处死大鼠，TUNEL法测定心肌凋亡指数，伊文斯兰一氯化三苯基四氮唑双染法测定心肌缺血面积和心肌梗死面积，分光光度法测定线粒体吸光度、心肌组织丙二醛（MDA）和超氧化物歧化酶（SOD）含量，Westernblot法测定凋亡途径信号分子Bcl-2、Bax和细胞色素c（Cyt—c）的表达水平。结果IP组大鼠右心房血浆pH值显著低于I／R组（P〈0．05），缺血心肌组织MDA含量显著低于I／R组（P〈0．05），SOD含量显著高于I／R组（P〈0．05）。Lac组和Lac＋Eda组右心房血浆pH值与IP组相似（7．32±0．07，7．32±0．04比7．33±0．03，P均〉0．05）。Eda组和Lac＋Eda组心肌组织MDA、SOD含量均与IP组相似[分别为（1．15±0．18），（1．17±0．12）比（1．12±0．37）nmol／mg蛋白，P均〉0．05，和（53±13），（53±16）比（58±13）U／mg蛋白，P均〉0．05]。Lac＋Eda组线粒体吸光度各时间点均显著高于I／R组（P均〈0．05），心肌组织Bcl-2含量显著高于I／R组（1．02±0．19比0．02±0．01，P〈0．05），Bax含量和胞浆中Cyt—c含量均显著低于I／R组（分别为0．38±0．07比2．40±0．45，P〈0．05，和0．78±0．05比6．54±1．86，P〈0．05），CK和CK-MB含量均显著低于I／R组[分别为（849±228）比（1249±211）U／L，P〈0．05，和（470Objective To test the hypothesis that pharmacological postconditioning with lactic acid and low dose edaravone could mimic the upper trigger of mechanical postconditioning and relieve reperfusion injury through mitochondrial pathway. Methods Rats were randomly divided into 6 groups （ n = 18 each） ： sham, reperfusion/injury （ I/R ） , postconditioning （ IP ） , lactic acid （ Lac, 60 μ1 ） , low dose edaravone （Eda, 3 μg/kg ）, and Lac ± Eda. After 45 min myocardial isehemia, different drugs or saline wereadministrated around the infarct border according to different groups using micro syringe at the time of reperfusion. After l0 min reperfusion, right atrial plasma pH value was determined in all rats. Then the rats were sacrificed at 1, 6 and 24 h （ n = 6 each）, apoptotie index was measured by TUNEL, infarct area and ischemic area were measured through Evans blue-TTC double staining, mitochondrial absorbance, the contents of MDA and SOD in ischemic myocardium were detected by spectrophotometry, and the expression of apoptotic pathway molecules, such as Bcl-2, Bax and Cytochrome c （ Cyt-c ） , were detected by Western blot. Results Right atrial plasma pH value was significantly lower, the content of MDA was significantly lower, and the content of SOD was significantly higher in IP and Lac ± Eda groups than in I/R group （ all P 〈 0. 05 ）. The mitochondrial absorbance in Lac ± Eda group at all time points were all significantly higher than those in I/R group （ all P 〈 0.05 ）. The level of Bcl-2 in ischemic myocardium in Lac ± Eda group was significantly higher than in I/R group （1.02 ±0. 19 vs. 0. 02 ±0.01, P 〈0.05）, the level of Bax （0. 38± 0. 07 vs. 2. 40 ± 0. 45, P 〈 0. 05 ） and Cyt-c （0.78 ± 0. 05 vs. 6. 54 ± 1.86, P 〈 0.05 ） were all lower than those in I/R group. The content of CK[（849 ±228） vs. （1249 ±211） U/L, P 〈0.05] and CK-MB [ （470 ± 266） vs. （966 ± 263 ） U/L, P 〈 0. 05 ] in Lac ± Eda group were all significantly l

关 键 词：心肌再灌注损伤 线粒体 心脏 乳酸 自由基清除剂 

分 类 号：R542.22[医药卫生—心血管疾病]