不同时间犬缺血心肌对^99Tc^m-MIBI摄取比值的观察

目的：观察犬冠状动脉左旋支狭窄后心肌细胞对^99碍^m-甲氧基异丁基异腈（^99Tc^m-MIBI）摄取与时间变化之间的关系。方法：建立犬冠状动脉左旋支狭窄模型（12只），分别注射^99Tc^m-MIBI，剂量为185MBq（5mCi）。注射1h和4h后，各处死6只犬，取出心脏，于左室侧壁（缺血区）和前壁（正常区）分别取心肌组织约100rag，用1计数器测定其放射性计数，换算成每克组织放射性计数值，求出侧壁与前壁放射性比值。结果：注射后1h犬左心室缺血区与正常区组织放射性计数比值为0．726±O．054，4h为0．673±0．080，两者之间比较差鼻无昂薯件（t=1．3452．P〉0．05）．结论．砸长时问不能摇高按血心肌对辨^99Tc^m-MIBI梧取比．

Observation on 99TCm-MIBI Uptake of Ischemic Myocardium in Dog Models Afcer Left Circumflex Coronary Artery Constriction

Objective To observe 99Tc^m= - MIBI uptake of ischemic myocardium at different times （ lh, 4h） in dog models after left circumflex coronary artery constriction. Methods 12 dog models of coronary artery stenesis were prepared by left circumflex coronary ligation, and were given injection of 99Tc^m= - MIBI at the dosage of 185 MBq （SmCi）. Six models were sacrificed at one hour and four hours after the injection respectively. Radio - uptake in about 100mg myocardium from both ischemic and non - ischemic sites were measured with r - counter. Results No significant differences were found between ratios of radioactive count of ischemic over normal myocardial tissues at lh and 4h after injection of 99Tc^m-MIBI （0. 726 ± 0. 054 and 0.673 ± 0.080, respective, t = 1. 3452, P 〉 0.05）. Conclusion The extension of pest - injection time would not increase 99Tc^m-MIBI uptake in ischemic myocardium.