¹⁸F-F13640 PET imaging of functional receptors in humans

Excerpt

The vast majority of PET radiopharmaceuticals used for receptor neuroimaging are antagonists. This is particularly true for 5-HT_1A receptor radiopharmaceuticals such as ¹⁸F-MPPF or ¹¹C-WAY100635. These radiolabeled antagonists allow PET neuroimaging of the total pool of receptors, regardless of their functional state. In contrast, agonists bind preferentially to the functionally active state of receptors, a pharmacological property that has not yet been exploited for PET imaging of functional 5-HT_1A receptors [1]. To this end, we have developed a highly selective 5-HT_1A receptor agonist, ¹⁸F-F13640, and validated it in animal models [2]. A postmortem study in Alzheimer subjects showed that the in vitro binding of ¹⁸F-F13640 differs from that of ¹⁸F-MPPF, the prototypical radiopharmaceutical [3]. …