放射性药物~(188)Re标记DTPA的制备和在大鼠体内的分布

球囊导管内充盈β放射性核素防治经皮冠状动脉成形术(PTCA)后再狭窄是一种崭新的技术, 其中,188Re是一种常用的放射性核素。为了尽可能降低在万一球囊破裂的情况下高剂量放射性对人体的损害,利用二乙三胺五醋酸(DTPA)迅速从泌尿系统排出的特点,通过探索188Re标记DTPA的方法和条件,成功地制备了188Re-DTPA化合物,并研究出最佳的标记条件从而使标记产率达到90%以上。188Re-DTPA和188ReO4-在大鼠体内分布的研究结果显示,甲状腺和胃肠道的放射性水平188Re-DTPA组明显低于188ReO4-组,188Re-DTPA经肾脏排泄明显快于188ReO4-,用MIRDOSE 3.0软件估算体内重要脏器的吸收剂量同样也显示了这一结果。188Re-DTPA组和188ReO4-组甲状腺的吸收剂量分别为0.041 nGy/Bq和0.563 nGy/Bq,胃的吸收剂量分别为0.043 nGy/Bq和0.118 nGy/Bq。因此,实验结果认为在血管内照射治疗中188Re-DTPA明显优于188ReO4-。

Preparation of radiopharmaceutical rhenium-188-labelled DTPA and its biodistribution in rats

A new method of preventing restenosis is the use of a liquid-filled balloon containing a beta-emitting radionuclide. Rhenium-188 is one of the most common used radionuclides. In order to reduce the injury caused by high dose radioactivity in the event of balloon rupture, we have succeeded in preparing the 188Re-DTPA compound because DTPA can be excreted from kidney rapidly. The labeling methods and conditions were described. The yield of 188Re-DTPA was more than 90%. The biodistribution studies of 188Re-DTPA and 188Re perrhenate showed that radioactivity levels of 188Re perrhenate in the thyroid gland and stomach were higher than that of 188Re-DTPA, and the excretion of 188Re-DTPA was much faster than that of 188Re perrhenate. Data of the estimated absorbed doses of various tissues in rats using software of MIRDOSE showed the same results. The thyroid radiation values in the 188Re-DTPA group and 188Re perrhenate group were 0.041 and 0.563nGy / Bq, respectively. And the stomach radiation values were 0.043 and 0.118nGy / Bq, respectively. Our study therefore suggested that 188Re-DTPA was superior to 188Re perrhenale for use in endovascular brachytherapy.