Ketamine displaces the novel NMDA receptor SPET probe [ 123I]CNS-1261 in humans in vivo

• Published in: Nuclear medicine and biology 2006-02, Vol.33 (2), p.239-243
• Main Authors: Stone, James M., Erlandsson, Kjell, Årstad, Erik, Bressan, Rodrigo A., Squassante, Lisa, Teneggi, Vincenza, Ell, Peter J., Pilowsky, Lyn S.
• Format: Article
• Language: English
• Subjects: [ 123I]CNS-1261; Adult; Brain - diagnostic imaging; Brain - metabolism; Cross-Over Studies; Guanidines - pharmacokinetics; Humans; Iodine Radioisotopes - pharmacokinetics; Ketamine; Ketamine - administration & dosage; Ketamine - pharmacokinetics; Male; Metabolic Clearance Rate; Molecular Probe Techniques; NMDA ion channel; Placebo Effect; Radiopharmaceuticals - pharmacokinetics; Receptors, N-Methyl-D-Aspartate - metabolism; Single photon emission tomography; Single-Blind Method; Tissue Distribution; Tomography, Emission-Computed, Single-Photon - methods
• ISSN: 0969-8051; 1872-9614
• DOI: 10.1016/j.nucmedbio.2005.12.001

[ 123I]CNS-1261 [ N-(1-naphthyl)- N′-(3-iodophenyl)- N-methylguanidine] is a high-affinity SPET ligand with selectivity for the intrachannel PCP/ketamine/MK-801 site of the N-methyl- d-aspartate (NMDA) receptor. This study evaluated the effects of ketamine (a specific competitor for the intrachannel PCP/ketamine/MK-801 site) on [ 123I]CNS-1261 binding to NMDA receptors in vivo. Ten healthy volunteers underwent 2 bolus-plus-infusion [ 123I]CNS-1261 scans, one during placebo and the other during a ketamine challenge. Ketamine administration led to a significant decrease in [ 123I]CNS-1261 V T in most of the brain regions examined ( P