Autoradiographic evaluation of [3H]CUMI-101, a novel, selective 5-HT1AR ligand in human and baboon brain

[C-11]CUMI-101 is the first selective serotonin receptor (5-HT1AR) partial agonist radiotracer for positron emission tomography (PET) tested in vivo in nonhuman primates and humans. We evaluated specific binding of [H-3]CUMI-101 by quantitative autoradiography studies in postmortem baboon and human brain sections using the 5-HT1AR antagonist WAY-100635 as a displacer. The regional and laminar distributions of [H-3]CUMI-101 binding in baboon and human brain sections matched the known distribution of [H-3]8-OH-DPAT and [H-3]WAY-100635. Prazosin did not measurably displace [H-3]CUMI-101 binding in baboon or human brain. sections, thereby ruling out [H-3]CUMI-101 binding to alpha 1-adrenergic receptors. This study demonstrates that [C-11]CUMI-101 is a selective 5-HT1AR ligand for in vivo and in vitro studies in baboon and human brain. (C) 2013 Elsevier B.V. All rights reserved.