title: In vitro evaluation of nicotinic acetylcholine receptors with 2-[18F]F-A85380 in Parkinson's disease.
abstract: Nicotinic acetylcholine receptors (nAChR) are involved in many physiological functions and appear to be affected in neurodegenerative diseases like Alzheimer's disease and Parkinson's disease (PD). Here, we describe the in vitro evaluation of nAChRs in PD with 2-[18F]F-A85380, a ligand with high affinity to the beta2 nAChR subunit. Autoradiography with 2-[18F]F-A85380 in untreated rat brain corresponded to the known distribution of alpha4beta2 nAChRs with high uptake in the thalamus, moderate uptake in the striatum and cortex and low uptake in the cerebellum (47%, 43% and 19% of the thalamus, respectively). The localization of alpha4beta2 nAChRs in the striatum was investigated in rodents with unilateral lesion of the substantia nigra. 2-[18F]F-A85380 binding was significantly reduced in the striatum ipsilateral to the lesion side (to 64% of the contralateral side), indicating that a fraction of alpha4beta2 nAChRs is located on dopaminergic terminals, whereas another fraction resides on striatal interneurons or cortical afferents. Similarly, in human brain sections of PD patients, 2-[18F]F-A85380 uptake was significantly reduced not only in the caudate and putamen but also in the thalamus (approximately 30% of the binding of control brain in all three regions); within the striatum, nAChRs in the putamen were significantly more severely affected as in the caudate. The observed pattern of alpha4beta2* nAChR loss demonstrates the potential of 2-[18F]F-A85380 for further investigations of this positron emission tomography ligand for in vivo studies of alpha4beta2* nAChRs in PD.
authors.affiliation: Department of Neurology, University of Bonn, Germany. joern.schmaljohann@ukb.uni-bonn.de
authors.forename: Jörn
authors.initials: J
authors.lastname: Schmaljohann
authors.forename: Daniela
authors.initials: D
authors.lastname: Gündisch
authors.forename: Martina
authors.initials: M
authors.lastname: Minnerop
authors.forename: Jan
authors.initials: J
authors.lastname: Bucerius
authors.forename: Alexius
authors.initials: A
authors.lastname: Joe
authors.forename: Michael
authors.initials: M
authors.lastname: Reinhardt
authors.forename: Stefan
authors.initials: S
authors.lastname: Guhlke
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Biersack
authors.forename: Ullrich
authors.initials: U
authors.lastname: Wüllner
mesh_terms: D000818:Animals; D001345:Autoradiography; D001384:Azetidines / Q000493:pharmacokinetics; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D005462:Fluorine Radioisotopes / Q000493:pharmacokinetics; D006801:Humans; D066298:In Vitro Techniques; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000378:metabolism*; D049268:Positron-Emission Tomography / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D011978:Receptors, Nicotinic / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: C104288:A 85380; D001384:Azetidines; D005462:Fluorine Radioisotopes; D011978:Receptors, Nicotinic