123I-5-IA-85380

**123I‑5‑IA‑85380** is a radiopharmaceutical used as a diagnostic imaging agent for single-photon emission computed tomography (SPECT) of the brain. It is a high-affinity, selective ligand for the α4β2 subtype of nicotinic acetylcholine receptors (nAChRs), which are widely distributed in the human brain and implicated in various neuropsychiatric and neurodegenerative disorders. The compound consists of an azetidine derivative (A‑85380) labeled with radioactive iodine‑123, enabling visualization and quantification of α4β2 nAChR density and distribution in vivo. Its mechanism involves binding to these receptors, allowing assessment of receptor availability or loss in conditions such as Parkinson's disease, Alzheimer's disease, mild cognitive impairment, drug dependence, and tobacco use disorder. The agent demonstrates rapid brain uptake, low nonspecific binding, minimal toxicity at tracer doses, and favorable dosimetry for clinical SPECT imaging[1][2][3][4][7].

Other names

[123I]5-I-A85380[123I]5-Iodo-A853803-(2S)-2-Azetidinylmethoxy)-5-Iodopyridine (radiolabeled with iodine‑123)