兔急性心肌梗死模型血运再通的实验研究

The Experiment Study of the Relationship of Blood Reperfusion and Sympathetic Nerve Impared Associated in Myocardial Infarction

目的:研究急性心肌梗死血运再通与心交感神经损伤关系。方法:完全闭塞12只雄性新西兰大白兔冠状动脉左前降支45min后血运再通4h,以131碘-间位碘代苄胍(131I-MIBG)、99m锝-甲氧基异丁基异腈(99mTc-MIBI)双核素放射自显影,并对照两种自显影与TTC组织染色间的联系。结果:血运再通4h,TTC组织染色面积缺损百分比小于无血运再通组,131I-MIBG及99mTc-MIBI自显影在同一区域摄取存在差异性,以急性无血运再通组,131I-MIBG缺损面积(38.8±3.1)%比组织TTC染色及99mTc-MIBI显影缺损大(P<0.001)。结论:急性无血运再通心肌梗死,心交感神经末梢颗粒损害敏感早而广,血运再通早能阻止神经损伤,本实验以MIBG显影,能够监测心肌梗死病变心交感神经活性改变。

Objective To investigated the relationship between blood reperfusion and sympathetic nervous injuring in acute myocardial infarction. Methods Autoradiography with ^131Iodine-Metaiodobenzylgnanidine （^131I-MIBG ） and ^99mTc-sestamibi （^99m Tc-MIBI） was performed in 12 male New Zealand White rabbits of which left anterior descending coronary artery was complete occluded for 45 min followed by 4 h blood reperfusion in acute myocardial infarction. Infarct areas identified by triphenyl tetrazolium chloride（TFC） staining and compared to the two autoradiography results. Results Whether Infarct areas, myocardi- al uptakes ^131I-MIBG and ^99m Tc-MIBI show defect larger than blood reperfusion groups, especially for non-blood reperfusion groups,^131I-MIBG autoradiaography imaging defected area （38.8 ±3.1% ） was larger than any other TTC staining and all of ^99mTc-MIBI imaging defect size （P 〈 0. 001 ）. Conclusion The experimental results suggests that sympathetic nerve injuring sensitive earlier and larger than myocardial infarction in non blood reperfused AMI. Blood reperfusion could protect sympathetic nervous from injury especiallyin AMI group; of which supports MIBG scintigraphy as a non-invasive tracer to measure sympathetic innervations changed and to provide powerful tools to assess the prognosis altered sympathetic nerve function in early AMI.