title: Synthesis of an I-123 analog of A-85380 and preliminary SPECT imaging of nicotinic receptors in baboon.
abstract: A radiosynthetic method to prepare the nicotinic acetylcholine receptor radioligand (S)-5-[123I]iodo-3-(2-azetidinylmethoxy)pyridine, 5-IA, has been developed. The two-step sequence produced [123I]-5-IA in high radiochemical yield (52%), high radiochemical purity (98%), and high specific radioactivities (> 8,500 mCi/mumol). Preliminary single photon emission computed tomography studies with [123I]-5-IA in baboon demonstrated the appropriate regional localization for a high-affinity nicotinic radioprobe (thalamus > frontal cortex > cerebellum). Pretreatment with cytisine blocked [123I]-5-IA uptake in all brain regions (78-59% reduction), demonstrating the specificity of the radiotracer.
authors: Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA. jlmusachio@petscan.nm.jhu.edu
authors: J L
authors: JL
authors: Musachio
authors: V L
authors: VL
authors: Villemagne
authors: U A
authors: UA
authors: Scheffel
authors: R F
authors: RF
authors: Dannals
authors: A S
authors: AS
authors: Dogan
authors: F
authors: F
authors: Yokoi
authors: D F
authors: DF
authors: Wong
mesh_terms: D000818:Animals; D001384:Azetidines / Q000138:chemical synthesis*; D001921:Brain / Q000000981:diagnostic imaging; D007457:Iodine Radioisotopes; D008297:Male; D015394:Molecular Structure; D010215:Papio; D011854:Radiochemistry; D011869:Radioligand Assay; D051381:Rats; D017207:Rats, Sprague-Dawley; D011978:Receptors, Nicotinic / Q000032:analysis*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: C104288:A 85380; D001384:Azetidines; D007457:Iodine Radioisotopes; D011978:Receptors, Nicotinic