新的^(99)Tc^mN配合物的制备及其生物分布研究

PREPARATION OF NEW ^(99)Tc^mN COMPLEXES FOR MYOCARDIAL IMAGING AND THEIR BIODISTRIBUTION IN MICE

为了寻找新的９９Ｔｃｍ Ｎ 标记的心肌显像剂，合成了两种含有酯基的ＮＳ配体半胱氨酸甲酯（ＣＹＭ）和半胱氨酸丙酯（ＣＹＰ）。以ＳｎＣｌ２ 为还原剂，Ｈ２ＮＮＨ－ （Ｃ＝ Ｓ）－ ＳＣＨ３ 为Ｎ３－ 给予体，通过交换反应制备了放化纯大于９０％ 的９９Ｔｃｍ Ｎ（ＣＹＭ）２ 和９９Ｔｃｍ Ｎ（ＣＹＰ）２。探讨了ｐＨ值和反应时间对９９Ｔｃｍ Ｎ配合物放化纯的影响，并对其在小鼠体内的生物分布进行了研究。结果表明，９９Ｔｃｍ Ｎ（ＣＹＭ）２ 和９９Ｔｃｍ Ｎ（ＣＹＰ）２在心肌中具有较高的初始摄取和快速的血清除，血半清除期小于１５ｍ ｉｎ。但是，心肌滞留不理想，心肌与其它组织的放射性比值较低。本工作对于设计新的９９Ｔｃｍ Ｎ心肌显像剂具有参考价值。

In order to seek new myocardial imaging agents labelled with 99 Tc mN core, two new 99 Tc mN complexes 99 Tc mN(CYM) 2 (L cysteine methyl ester hydrochloride)and 99 Tc mN(CYP) 2 (L cysteine propyl ester hydrochloride)have been prepared and evaluated for potential use in myocardial perfusion imaging. Their labeling conditions are also investigated. In their biodistribution studies in mice, high myocardial uptake and rapid clearance from blood are demonstrated. The clearance half life of both 99 Tc mN complexes are less than 15 min. However, the retention of activity in heart of two 99 Tc mN complexes are not long. At 30 min post injection, only 0.19%(ID) of 99 Tc mN(CYM) 2 and 0.27%(ID) of 99 Tc mN(CYP) 2 retained respectively in heart. The formation of two 99 Tc mN complexes are rapid with high yield(>90%). This study could be valuable to design of new 99 Tc mN myocardial imaging agents.