心肌声学造影定量评价硝酸甘油对犬顿抑心肌的延迟保护作用  

Evaluation of Nitroglycerin Protection Effect on Myocardial Stuning Using Myocardial Contrast Echocardiography

作　　者：李玉宏[1] 杨军[1] 唐力[1] 马春燕[1] 陈昕[1] 章志伟[1] 任卫东[1] 

机构地区：[1]中国医科大学第一临床学院心功能科,沈阳市110001

出　　处：《中国超声医学杂志》2005年第4期244-248,共5页Chinese Journal of Ultrasound in Medicine

摘　　要：目的　探讨心肌声学造影技术( myocardial contrast echocardiography,MCE)定量评价硝酸甘油对犬顿抑心肌微血管内皮功能延迟保护作用的价值。方法　1 2只健康成年杂种犬随机分成缺血再灌注组( A组)和硝酸甘油组( B组)。A组不给予任何药物,保持基础状态,单纯进行左冠状动脉前降支结扎2 0 min,再灌注1 2 0 min,分别于缺血及再灌注时弹丸式注射自制含氟碳气体的微泡声学造影剂进行MCE。B组用微量静脉泵以2 μg/ ( kg.min)速度静滴硝酸甘油1 h,2 4 h后结扎左冠状动脉前降支,其余步骤同A组。在不同观测时间点分别经主动脉根部注射乙酰胆碱( acetylcholine,ACH) 1 0 μg/ kg,于注射前和注射后4 0～5 0 s重复心肌声学造影。在ADT- INT状态下于左室乳头肌水平短轴切面测定左冠状动脉前降支供血区域的心肌层内心肌视频密度时间-强度曲线参数,每次实验结束后,将心肌组织进行伊文思蓝( Evans blue,EB )及红四氮唑( triphenyl tetrazolium chloride,TTC)心肌组织染色。结果　两组顿抑心肌的峰值声强度、时间-强度曲线下面积比正常心肌明显减低,差异有显著性,B组在再灌注即刻、3 0、6 0、90 min时峰值声强度及曲线下面积均高于A组,差异有显著性意义,B组比A组更快恢复至正常水平。再灌注后两组的ACH- PIR显著降低。Objective To investigate the nitroglycerin protective ischemic preconditioning effect on myocardial stuning using myocardial contrast echocardiography(MCE).Methods Twelve anaesthetized dogs were randomly divided into two groups:ischemia and reperfusion (group A) and nitroglycerin (group B).In group A,the anterior descending coronary artery was blocked for 20 minutes,subsequently,and reperfused for 120 minutes.Then MCE was performed during reperfusion in 0,30,60,90,120 min.In group B nitroglycerin was given with the speed of 2μg/( kg.min) intravenously,after 24 hours by fo1lowed the same step as the group A .During ischemia and reperfusion the parameters of time-intensity curve were measured in corresponding regional myocardium using AD technique before and after acetylcholine(ACH) injection. Gross patho1ogic specimen was stained with triphenyl tetrazolium chloride(TTC) after test.Results The peak intensity(PI), area under the curve(AUC) and endothelium-dependent relaxation (EDR) in myocardial stuning were significantly decreased versus in the normal myocardium (P<0.05),which was increased gradually with the prolonging reperfusion duration,in addition,which recovered faster in group B then in group A.Conclusions Microvascular blood flow and EDR in myocardial stuning were injuried. Intermittent second harmonic MCE using intravenous injection of perfluorocarbon microbubbles could assess nitroglycerin protection on myocardial stunning.

关 键 词：延迟保护作用 心肌声学造影 顿抑心肌 定量评价 冠状动脉前降支 依赖性舒张功能减弱 血管内皮功能 微泡声学造影剂 曲线下面积 声学造影技术 静滴硝酸甘油 内皮功能受损 缺血再灌注 成年杂种犬 含氟碳气体 主动脉根部 左室乳头肌 

分 类 号：R96[医药卫生—药理学]