Van Nerom C G, Bormans G M, De Roo M J, Verbruggen A M
Department of Nuclear Medicine, U.Z. Gasthuisberg, Leuven, Belgium.
Eur J Nucl Med. 1993 Sep;20(9):738-46. doi: 10.1007/BF00180902.
Animal studies have indicated that technetium-99m L,L-ethylenedicysteine (99mTc-L,L-EC) may be a promising tracer agent for renal function studies. We have performed a paired study with 99mTc-mercaptoacetyltriglycine (99mTc-MAG3) and 99mTc-L,L-EC in six male volunteers. In both cases, iodine-131-labelled o-iodohippurate was co-injected as an internal biological standard. The analog images between 0 and 30 min p.i. were of identical diagnostic value for both tracer agents. The two renograms were similar in all volunteers. The mean 1-h plasma clearance for 99mTc-MAG3 and 99mTc-L,L-EC was significantly different, respectively 382.9 +/- 17.1 ml/min per 1.73 m2 versus 460.2 +/- 47.7 ml/min per 1.73 m2 (P < 0.003). The urinary excretion after 30 min p.i. was 69.4% +/- 5.6% of the injected dose for 99mTc-MAG3 versus 66.5% +/- 2.5% for 99mTc-L,L-EC (P > 0.05) and after 60 min p.i. respectively 83.1% +/- 3.9% versus 79.8% +/- 4.3% (P > 0.05). 99mTc-L,L-EC has a very low plasma protein binding (31% +/- 6.8%) as compared to 99mTc-MAG3 (88% +/- 5.2%) and a larger volume of distribution. Although the exact mechanism responsible for the high plasma clearance of 99mTc-L,L-EC is not yet fully known, we conclude that this new agent merits further clinical evaluation in patients to establish its value as a renal radiopharmaceutical.
动物研究表明，锝-99m L,L-乙二巯基丁二酸（99mTc-L,L-EC）可能是一种用于肾功能研究的有前景的示踪剂。我们在6名男性志愿者中对99mTc-巯基乙酰三甘氨酸（99mTc-MAG3）和99mTc-L,L-EC进行了配对研究。在这两种情况下，均同时注射碘-131标记的邻碘马尿酸作为体内生物标准。注射后0至30分钟之间的模拟图像对两种示踪剂具有相同的诊断价值。所有志愿者的两条肾图相似。99mTc-MAG3和99mTc-L,L-EC的平均1小时血浆清除率有显著差异，分别为每1.73 m2 382.9±17.1 ml/分钟和每1.73 m2 460.2±47.7 ml/分钟（P<0.003）。注射后30分钟时，99mTc-MAG3的尿液排泄量为注射剂量的69.4%±5.6%，而99mTc-L,L-EC为66.5%±2.5%（P>0.05）；注射后60分钟时，分别为83.1%±3.9%和79.8%±4.3%（P>0.05）。与99mTc-MAG3（88%±5.2%）相比，99mTc-L,L-EC的血浆蛋白结合率非常低（31%±6.8%），且分布容积更大。尽管导致99mTc-L,L-EC高血浆清除率的确切机制尚未完全明确，但我们得出结论，这种新制剂值得在患者中进行进一步的临床评估，以确定其作为肾放射性药物的价值。
