Neirinckx R D, Canning L R, Piper I M, Nowotnik D P, Pickett R D, Holmes R A, Volkert W A, Forster A M, Weisner P S, Marriott J A
J Nucl Med. 1987 Feb;28(2):191-202.
Following investigation of a large number of new ligands based upon propylene amine oxime (PnAO) the d,l-diastereoisomer of hexamethyl propyleneamine oxime (HM-PAO) was selected as the preferred ligand for 99mTc as a tracer for cerebral perfusion imaging. The neutral, lipophilic 99mTc complex of d,l-HM-PAO was formed in high yield by stannous reduction of 99Mo/99mTc generator eluate using a kit formulation of the ligand. Two minutes following i.v. administration of this complex in rats, 2.25% of the injected dose appears in the brain. Little washout of the tracer is observed up to 24 hr postinjection. By qualitative autoradiographic comparison with iodoantipyrine this new radiopharmaceutical displays blood flow dependent brain uptake with little redistribution of the tracer over time. The lipophilic 99mTc complex converts slowly in vitro to a secondary complex. This conversion process may account for the ability of [99mTc]d,l-HM-PAO to be retained within the brain without redistribution.
在对大量基于丙二胺肟（PnAO）的新配体进行研究之后，六甲基丙二胺肟（HM-PAO）的d，l-非对映异构体被选为用于脑灌注显像的99mTc的首选配体。使用该配体的试剂盒配方，通过用亚锡还原99Mo/99mTc发生器洗脱液，以高产率形成了d，l-HM-PAO的中性亲脂性99mTc络合物。在大鼠静脉注射该络合物两分钟后，2.25%的注射剂量出现在脑中。在注射后长达24小时内，几乎未观察到示踪剂的洗脱。通过与碘安替比林的定性放射自显影比较，这种新的放射性药物显示出与血流相关的脑摄取，且示踪剂随时间几乎没有重新分布。亲脂性99mTc络合物在体外缓慢转化为二级络合物。这种转化过程可能解释了[99mTc]d，l-HM-PAO在脑内保留而不重新分布的能力。
