【摘要】 目的 [二（二甲氧丙基膦基乙基）-乙氧乙胺]-[二（氧-乙氧乙基）二硫代氨基]锝氮配合物[^99mTc（N）（PNP5）（DBODC）]⁺是新近开发出的一种心肌灌注显像剂,前期研究显示,其具有显著的肝清除速度。本研究观察其在犬急性心肌缺血模型中的显像特点,并与^99mTc-MIBI 进行比较。方法 12只实验用纯种比格犬随机分为两组。组1,手术阻断左冠状动脉前降支血流,制成冠状动脉狭窄>90%后,静脉滴注腺苷,0.14 mg·kg^-1·min^-1,共6 min,3 min 末时注射[^99mTc（N）（PNP5）（DBODC）]⁺185 MBq。腺苷滴注完毕后,解除血管阻断,恢复心肌供血。分别于注射显像剂后0.5、1、1.5、2 h 进行心肌灌注单光子发射计算机断层（SPECT）显像,24 h 后行静息心肌 SPECT 显像。组2,除注射的显像剂为^99mTc-MIBI 外,其余实验方案同组1。结果 [^99mTc（N）（PNP5）（DBODC）]⁺的心肌摄取高,滞留时间长,其心肌摄取与^99mTc-MIBI 相当。两者的肺摄取均很低,0.5 h 时[^99mTc（N）（PNP5）（DBODC）]⁺和^99mTc-MIBI 的心/肺比值分别为3.55±0.68和2.92±0.32,且2 h 内无显著变化。但[^99mTc（N）（PNP5）（DBODC）]⁺的肝清除速度显著快于^99mTc-MIBI,注射后1 h,[^99mTc（N）（PNP5）（DBODC）]⁺的心/肝比值已显著高于^99mTc-MIBI（1.36±0.43比0.58±0.21,P=0.005）。[^99mTc（N）（PNP5）（DBODC）]⁺能清晰显示心肌缺血,其检测心肌缺血的效能不差于^99mTc-MIBI,[^99mTc（N）（PNP5）（DBODC）]⁺显示缺损节段（3.60±1.52）个,^99mTc-MIBI 显示缺损节段（4.25±0.96）个,P=0.48。[^99mTc（N）（PNP5）（DBODC）]⁺具有和^99mTc-MIBI 相似的轻度"再分布"特性。由于肝清除迅速,早期显像（注射后30 min）时,[^99mTc（N）（PNP5）（DBODC）]⁺的图像质量优于^99mTc-MIBI。结论 [^99mTc（N）（PNP5）（DBODC）]⁺作为一种新型心肌灌注显像剂,其心肌摄取、肺摄取、检测心肌缺血的效能以及"再分布"特性等均与^99mTc-MIBI 相似,同时其肝清除速度显著快于^99mTc-MIBI,这不仅有利于实现早期显像,而且避免了肝摄取对左心室下后壁的干扰,从而利于更准确地诊断冠心病。故[^99mTc（N）（PNP5）（DBODC）]⁺具有进一步进行临床研究的价值。更多还原

【Abstract】 Objective ^99mTe-[ bis（dimethoxypropylphosphinoethyl）-ethoxyethylamine（PNP5）1- [bis（N-ethoxyethyl）-dithioearbamato（DBODC）]nitride([^99mTc（N）（PNP5）（DBODC）1⁺)is a new myocardial perfusion tracer with high heart uptake and rapid liver clearance.The objectives of this study were to compare the myocardial imaging of[^99mTc（N）（PNP5）（DBODC）]⁺with ^99mTc-MIBI in a canine model of acute myocardial ischemia.Methods The left anterior descending artery（LAD）was occluded in 12 adult beagle dogs,adenosine was then infused intravenously at a rate of 0.14 mg·kg^-1·min^-1for 6 min.At the end of 3 min of adenosine infusion,185 MBq of[ ^99mTC（N）（PNP5）（DBODC）]+or ^99mTc- MIBI was injected intravenously.The occluder was released after 6 min adenosine infusion.Serial myocardial SPECT imaging acquisitions were obtained at 0.5,1,1.5 and 2 h after tracer injection, respectively.Rest myocardial SPECT imaging was acquired in the next day.Results Similar as ^99mTc- MIBI,[ ^99mTc（N）（PNP5）（DBODC）]⁺exhibited high heart uptake,minimal lung uptake and minimal redistribution.No significant myocardial washout was observed with both tracers over a period of 2 hours. [ ^99mTc（N）（PNP5）（DBODC）]⁺clearance from the liver was more rapid than that with ^99mTc-MIBI（heart- liver radio at 60 min,1.36±0.43 vs.0.58±0.21,P=0.005）.[ ^99mTC（N）（PNP5）（DBODC）]⁺the ability to detect myocardial ischemia was also comparable between the two tracers([^99mTc（N）（PNP5） （DBODC）]⁺detected 3.60±1.52 defect segments,^99mTc-MIBI detected 4.25±0.96 defect segments,P =0.48).The image quality of[^99mTc（N）（PNP5）（DBODC）]⁺was better than ^99mTc-MIBI.Conclusion [ ⁹99m)Tc（N）（PNP5）（DBODC）]⁺is comparable to ^99mTc-MIBI on detecting myocardial ischemia in this model and liver clearance is more rapid and the image quality is better than ^99mTc-MIBI.更多还原