右美托咪定对老龄大鼠在体心肌缺血再灌注损伤的影响  

Effects of Dexmedetomidine on Vivo Aged Rat Heart of Ischaemia Reperfusion Injury

作　　者：董婧[1] 郭昕[1] 李晟阳[2] 崔基贤[3] 于学武[3] 张雅楠[1] 李林[1] 

机构地区：[1]沈阳农业大学畜牧兽医学院,沈阳110164 [2]沈阳农业大学出版部,沈阳110161 [3]辽宁省动物疫病预防控制中心/辽宁省动物医学研究院,沈阳110164

出　　处：《沈阳农业大学学报》2015年第5期555-560,共6页Journal of Shenyang Agricultural University

基　　金：国家自然科学基金项目(31302149)

摘　　要：为研究在体缺血再灌注过程对老龄大鼠造成的损伤以及右美托咪定预处理对老龄大鼠在体心肌缺血再灌注损伤的影响。选取40只老龄雄性健康SD老龄大鼠,将其随机分成4组(n=10):右美托咪定预处理组(D-P组)、缺血预适应组(I-P组)、缺血再灌注损伤组(I-R组)、假手术组(C-S组)。在老龄大鼠的右侧分离出颈动脉,并行左心室置管,对老龄大鼠的左心功能变化进行记录,连接心电图选用标准II导联方式,记录波形变化。通过记录缺血再灌注前后不同时间点HR和心功能指标±dp/dtmax,测量超氧化物歧化酶(SOD)活性和心肌中丙二醛(MDA)的含量;然后对再灌注末心肌梗死面积进行计算。结果表明:老龄大鼠开胸后,随着时间的增加,每组的平均动脉压及心率都有下降趋势。相比C-S组,I-R组平均动脉压及心率都显著降低(p<0.05),D-P组的心率在给药后就开始下降显著,但与I-R组对比平均动脉压下降不明显,尤其是在再灌注末期,平均动脉压D-P组要高于I-R组,组间差异显著。对比C-S组,在I-R组中老龄大鼠的左心功能各指标显示降低的左心功能,I-R组和C-S组的组间差异是显著的。相对于I-R组,D-P组±dp/dtmax升高。与C-S组相比,I-R组MDA含量在心肌组织匀浆中增高,SOD活性下降(p<0.05);对比I-R组,心肌组织匀浆中MDA含量在D-P组增高,SOD活性下降(p<0.05)。缺血再灌后对老龄大鼠在体心肌明显损伤,通过右美托咪定预处理可使老龄大鼠在体心肌缺血再灌注损伤得到有效减轻,对在一定程度上保护老龄大鼠的心脏。The effect old of dexmedetomidine on myocardial ischemia-reperfusion injury in aged rats was studied. 40 healthy male,250-300 g SD aged rats were divided into four groups randomly（n=10）： group of ischemic preconditioning（I-P group）, group of Sham（C-S group）,group of dexmedetomidine（D-P group）,ischemia-reperfusion injury group（I-R group）. The right carotid artery of the aged rats were separated and functions of the left ventricular were recorded, and the electrocardiogram by selecting standard II lead connection was recorded. The date of ±dp/dtmax and HR were detected before and after the occurrance of ischemia-reperfusion. SOD and MDA activities were recorded. Myocardial infarct size was calculated at the end of reperfusion. The result showed that HR in each group decreased after thoracotomy. The I-R group heart rate compared with C-S group（p〈0.05）. After given dexmeditomidine, HR in the D-P group began to decreased significantly. Left heart function in I-R group compared with the C-S group showed that a statistically reduce of left ventricular function. SOD activity decreased and MDA in myocardial tissue homogenates increased in I-R group（p〈0.05）.SOD activity in D-P group compared with I-R group decreased,MDA increased（p〈0.05）. Myocardial injury of aged rats can be leaded by myocardial ischemiareper fusion in vivo. Dexmedetomidine has a protective effect on heart of aged rat.

关 键 词：心肌缺血 再灌注损伤 老龄大鼠 缺血预处理 右美托咪定 

分 类 号：Q956[生物学—动物学]