Prata M I, Santos A C, Geraldes C F, de Lima J J
Serviço de Biofísica e Biomatemática, Fac. Medicina, Universidade de Coimbra, Portugal.
Nucl Med Biol. 1999 Aug;26(6):707-10. doi: 10.1016/s0969-8051(99)00041-4.
The 67Ga3+ complexes of three triazamacrocycles, 1,4,7-triazacyclononane-N,N',N''-triacetic acid (NOTA), its phosphonate analog 1,4,7-triazacyclononane-N,N',N''-tris(methylenephosphonic) acid (NOTP), and the monoethyl ester of NOTP, 1,4,7-triazacyclononane-N,N',N''-tris (methylenephosphonate-monoethylester) (NOTPME) were studied for possible use as radiopharmaceuticals. Biodistribution studies and gamma imaging were performed in Wistar rats. The present results demonstrated that all the macrocyclic complexes studied display renal clearance and are almost completely eliminated within 24 h. The 67Ga3- chelate, with a large negative charge, has a considerably slower uptake and elimination by the kidneys than the neutral 67Ga and 67Ga chelates. We have thus demonstrated a charge-clearance relationship for a series of stable and well characterized complexes. The high stability and rapid renal excretion properties displayed by the NOTA and NOTPME chelates support their possible application as imaging agents for kidney structural and functional studies.
研究了三种三氮杂大环化合物1,4,7-三氮杂环壬烷-N,N',N''-三乙酸（NOTA）、其膦酸酯类似物1,4,7-三氮杂环壬烷-N,N',N''-三（亚甲基膦酸）（NOTP）以及NOTP的单乙酯1,4,7-三氮杂环壬烷-N,N',N''-三（亚甲基膦酸单乙酯）（NOTPME）的67Ga3+配合物作为放射性药物的潜在用途。在Wistar大鼠身上进行了生物分布研究和γ成像。目前的结果表明，所研究的所有大环配合物均显示出经肾脏清除，并且在24小时内几乎完全消除。带有大量负电荷的67Ga3-螯合物，其被肾脏摄取和消除的速度比中性的67Ga和67Ga螯合物要慢得多。因此，我们证明了一系列稳定且特征明确的配合物的电荷-清除关系。NOTA和NOTPME螯合物所表现出的高稳定性和快速肾脏排泄特性支持它们作为肾脏结构和功能研究的成像剂的潜在应用。
