当前位置： SCI文献检索 > NUCLEAR MEDICINE AND BIOLOGY期刊下所有文献 > Radiochemical synthesis and in vivo evaluation of [18F]AZ11637326: an agonist probe for the α7 nicotinic acetylcholine receptor.

Radiochemical synthesis and in vivo evaluation of [18F]AZ11637326: an agonist probe for the α7 nicotinic acetylcholine receptor.

Abstract：

INTRODUCTION:The alpha-7 nicotinic acetylcholine receptor (α7 nAChR) is key in brain communication and has been implicated in the pathophysiology of diseases of the central nervous system. A positron-emitting radioligand targeting the α7 nAChR would enable better understanding of a variety of neuropsychiatric illnesses, including schizophrenia and Alzheimer's disease, and could enhance the development of new drugs for these and other conditions. We describe our attempt to synthesize an α7 nAChR-selective radiotracer for positron emission tomography (PET). METHODS:We prepared the high-affinity (K(d) = 0.2 nM) α7 nAChR agonist, 5'-(2-[(18)F]fluorophenyl)spiro[1-azabicyclo-[2.2.2]octane]-3,2'-(3'H)furo[2,3-b]pyridine, [(18)F]AZ11637326, in two steps, a nucleophilic fluorination followed by decarbonylation. We studied [(18)F]AZ11637326 in rodents, including mice lacking α7 nAChR, and in non-human primates. RESULTS:[(18)F]AZ11637326 was synthesized in a non-decay-corrected radiochemical yield of 3% from the end of synthesis (90 min) with a radiochemical purity >90% and average specific radioactivity of 140GBq/μmol (3,781 mCi/μmol). Modest rodent brain uptake was observed (2-5% injected dose per gram of tissue, depending on specific activity), with studies comparing CD-1 and α7 nAChR null mice indicating an element of target-specific binding. Blocking studies in non-human primates did not reveal specific binding within the brain. CONCLUSION:Despite the high affinity and target selectivity of AZ11637326 for α7 nAChR in vitro and encouraging rodent studies, receptor-mediated binding could not be demonstrated in non-human primates. Further structural optimization of compounds of this class will be required for them to serve as suitable radiotracers for PET.

journal_name

Nucl Med Biol

journal_title

Nuclear medicine and biology

authors

Ravert HT,Dorff P,Foss CA,Mease RC,Fan H,Holmquist CR,Phillips E,McCarthy DJ,Heys JR,Holt DP,Wang Y,Endres CJ,Dannals RF,Pomper MG

doi

10.1016/j.nucmedbio.2013.04.005

subject

Has Abstract

pub_date

2013-08-01 00:00:00

pages

731-9

issue

eissn

0969-8051

issn

1872-9614

pii

S0969-8051(13)00078-4

journal_volume

pub_type

杂志文章

在线工具

Radiochemical synthesis and in vivo evaluation of [18F]AZ11637326: an agonist probe for the α7 nicotinic acetylcholine receptor.