摘要
目的 探讨简易制备和纯化多巴胺转运蛋白 (DAT)显像剂1 8F N (3 氟丙基 ) 2 β 甲酯基 3β (4′ 碘苯基 )去甲基托烷 (1 8F FP β CIT)的方法 ,进行大鼠脑内分布研究。方法 采用一步法标记 ,在氨基聚醚 (Kryptofix 2 2 2 )催化下 ,标记前体化合物N 3 (甲磺酰氧基丙基 ) 2 β 甲酯基 3β (4 碘苯基 )去甲基托烷 (MsOP CIT)直接与K1 8F在乙腈溶液中反应 ,生成1 8F FP β CIT ,用Sep PakSiO2 小柱分离纯化。大鼠给药后于不同时间处死 ,分离脑组织 ,分别称重后测定放射性计数。结果 1 8F FP β CIT总放化产率约为 10 % ,放化纯 >95 % ,纯化无需制备型高效液相色谱。总合成时间为 6 0～ 80min。药物能迅速被脑组织摄取 ,后不断清除 ,5和 180min时全脑摄取量 (%ID)分别为 1.4 9和 0 .17。纹状体放射性摄取大于其他区域 ,其与小脑的比值在 5、30、6 0、12 0和 180min时分别为 1.75、3.38、3.73、3.71和 3.2 0。结论 一步法可简便制得1 8F FP β CIT。
Objective To develop a simple and easy protocol of preparing 18F-N-3-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)nortropane (FP-β-CIT) as a dopamine transporter imaging agent, and to study the distribution of this agent in rat brain. Methods 18F-FP-β-CIT was prepared by direct reaction in CH 3CN between K 18F and the labeling precursor, N-(3-(mesyloxy)propyl)-2β-carbomethoxy-3β-(4-iodophenyl)nortropane (MsOP-CIT), in which Kryptofix 222 was used as phase transfer catalyst. 18F-FP-β-CIT was purified through a Sep-Pak SiO 2 cartridge and eluted with ethyl ether. The purified 18F-FP-β-CIT was injected into the rat's tail vein. These rats were sacrificed by cervical dislocation at different time points (5, 30, 60, 120, 180 min) after injection. The brain tissue of interest was removed, weighed, and radiocounted. Results The radiochemical purity of 18F-FP-β-CIT was over 95%, and the radiochemical yield from starting 18F-fluoride was about 10%. 18F-FP-β-CIT was absorbed rapidly in rat brain and was cleaned gradually(1.49, 0.59, 0.31, 0.21, 0.17%ID at 5, 30, 60, 120, 180 min, respectively). Radiouptake of striatum was more than that of other tissues and was cleaned slower than in other tissues at 60 min. Ratios of radiouptake of striatum/cerebellum were 1.75, 3.38, 3 73, 3.71 and 3.20 at 5, 30, 60, 120, 180 min, respectively. Conclusions 18F-FP-β-CIT is synthesized by a one-step protocol in which the preparative high performance liquid chromatography is not necessary in purifying procedure. The dominent distribution of 18F-FP-β-CIT in rat striatum indicates that it is a potential dopamine transporter imaging agent.
出处
《中华核医学杂志》
CAS
CSCD
北大核心
2003年第4期241-243,共3页
Chinese Journal of Nuclear Medicine
基金
江苏省卫生厅重点科研基金资助项目 (H2 0 0 8)
