title: Development and evaluation of muscarinic cholinergic receptor ligands N-[11C]ethyl-4-piperidyl benzilate and N-[11C]propyl-4-piperidyl benzilate: a PET study in comparison with N-[11C]methyl-4-piperidyl benzilate in the conscious monkey brain.
abstract: The muscarinic cholinergic receptor ligands N-[(11)C]ethyl-4-piperidyl benzilate (4-EPB) and N-[(11)C]propyl-4-piperidyl benzilate (4-PPB) were developed and evaluated in comparison with N-[(11)C]methyl-4-piperidyl benzilate (4-MPB) in the conscious monkey brain using positron emission tomography (PET). Time-activity curves of [(11)C]4-EPB, unlike [(11)C]4-MPB, showed peaks within 91 min in regions rich in muscarinic receptors. [(11)C]4-PPB showed no specific binding even in the regions rich in these receptors. These observation demonstrated that increases in [(11)C]alkyl chain length could alter the kinetic properties of receptor ligands for PET.
authors.affiliation: Central Research Laboratory, Hamamatsu Photonics K. K., Hamakita, Shizuoka, Japan
authors.forename: S
authors.initials: S
authors.lastname: Nishiyama
authors.forename: K
authors.initials: K
authors.lastname: Sato
authors.forename: N
authors.initials: N
authors.lastname: Harada
authors.forename: T
authors.initials: T
authors.lastname: Kakiuchi
authors.forename: H
authors.initials: H
authors.lastname: Tsukada
mesh_terms: D000818:Animals; D001561:Benzilates / Q000378:metabolism*; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism; D007553:Isotope Labeling; D008024:Ligands; D008253:Macaca mulatta; D008279:Magnetic Resonance Imaging; D008297:Male; D010880:Piperidines / Q000378:metabolism*; D019275:Radiopharmaceuticals / Q000378:metabolism*; D011976:Receptors, Muscarinic / Q000378:metabolism*; D014055:Tomography, Emission-Computed
chemical_list: D001561:Benzilates; D008024:Ligands; C422382:N-ethyl-4-piperidyl benzilate; C422185:N-propyl-4-piperidyl benzilate; D010880:Piperidines; D019275:Radiopharmaceuticals; D011976:Receptors, Muscarinic; C020407:enpiperate