Synthesis and autoradiographic localization of muscarinic cholinergic antagonist (+)N-[C-11]methyl-3-piperidyl benzilate as a potent radioligand for positron emission tomography

: Takahashi K, Murakami M, Miura S, Iida H, Kanno I, Uemura K

Publisher: PERGAMON-ELSEVIER SCIENCE LTD

: 1999

: Applied Radiation and Isotopes

: APPLIED RADIATION AND ISOTOPES

: APPL RADIAT ISOTOPES

: 50

: 3

: 521

: 525

: 5

: 0969-8043

DOI: https://doi.org/10.1016/S0969-8043(97)10155-5

(+)N-[C-11]methyl-3-piperidyl benzilate, a relatively low affinity muscarinic cholinergic receptor antagonist was synthesized by N-[C-11]methylation of (+)3-piperidyl benzilate using [C-11]methyl iodide. The product was isolated by HPLC, and obtained with radiochemical yield of 60-70% from [C-11]methyl iodide, and a specific activity of 500-1000 Ci mmol(-1) (18.5-37 GBq mu mol(-1)) at EOS and radiochemical purity of >98%. In vitro autoradiographic studies showed selective binding for this radiotracer in the different regions of the rat brain: high in corpus striatum, hippocampus and cerebral cortex, and low in cerebellum, consistent with muscarinic cholinergic receptor distributions. This radiotracer thus had potential as radioligand for positron emission tomography. (C) 1999 Elsevier Science Ltd. All rights reserved.