作者:Ola Åberg、Marc Stevens、Jonas Lindh、Charlotta Wallinder、Håkan Hall、Azita Monazzam、Mats Larhed、Bengt Långström
DOI:10.1002/jlcr.1793
日期:——
Three 11C-radiolabelled high-affinity nonpeptide AT2 receptor-selective ligands were synthesized and one of these was evaluated as positron emission tomography (PET) tracer. The labelling reaction was performed via palladium(0)-mediated aminocarbonylation of the aryl iodide substrate using [11C]carbon monoxide as the labelled precursor. As an example, starting with 10.0 GBq [11C]carbon monoxide, 1.10 GBq of the product N-butoxycarbonyl-3-[4-(N-benzyl-[11C]carbamoyl)-phenyl]-5-isobutylthiophene-2-sulphonamide [11C]4d was obtained in 36% decay-corrected radiochemical yield (from [11C]carbon monoxide), 42 min from end of bombardment with a specific activity of 110 GBq·µmol−1. The N-isopropyl-[11C]carbamoyl-analogue [11C]4c (radiochemical purity >95%) was studied employing autoradiography, organ distribution, and small animal PET. In vitro autoradiography showed specific binding in the pancreas and kidney. Organ distribution in six rats revealed a high uptake in the liver, intestine, kidney, and adrenals. Small animal PET showed rapid and reversible uptake in the kidneys followed by accumulation in the urinary bladder suggesting fast renal excretion of the tracer. In addition, high accumulation was also seen in the liver. For future studies, more metabolically stable tracers will need to be developed. To the best of our knowledge, this is the first attempt of the use of PET imaging for the detection of expressed, fully functional AT2 receptors in living subjects. Copyright © 2010 John Wiley & Sons, Ltd.
合成了三种11C放射性标记的高亲和力非肽AT2受体选择性配体,其中一种被评估作为正电子发射断层扫描(PET)示踪剂。标记反应是通过使用[11C]一氧化碳作为标记前体的钯(0)催化氨基羧基化反应在芳基碘化合物底物上进行的。以10.0 GBq [11C]一氧化碳为起始材料,获得了产物N-丁氧羧基-3-[4-(N-苄基-[11C]氨甲酰基)-苯基]-5-异丁基噻吩-2-磺酰胺[11C]4d,衰变校正的放射化学产率为36%(来自[11C]一氧化碳),从轰击结束算起42分钟,具有110 GBq·µmol−1的特定活性。N-异丙基-[11C]氨甲酰基类似物[11C]4c(放射化学纯度 >95%)通过自显影、器官分布和小动物PET进行研究。在体外自显影显示在胰腺和肾脏有特异性结合。在六只大鼠中的器官分布显示肝脏、肠道、肾脏和肾上腺的摄取量较高。小动物PET显示肾脏快速且可逆的摄取,随后在膀胱聚集,这表明示踪剂的快速肾排泄。此外,肝脏也显著聚集。在未来的研究中,需要开发更具代谢稳定性的示踪剂。据我们所知,这是首次尝试在活体中使用PET成像技术检测已表达的、完全功能的AT2受体。版权 © 2010 John Wiley & Sons, Ltd.