Pet imaging studies of dopamine D2 receptors: Comparison of [18F]N‐Methylspiperone; and the benzamide analogues [18F]MABN and [18F]MBP in baboon brain
- 1 March 1995
- Vol. 19 (3) , 177-187
- https://doi.org/10.1002/syn.890190305
Abstract
A series of positron emission tomography (PET) imaging studies was conducted in a baboon with the benzamide derivatives [18F]2,3‐dimethoxy N‐9‐(4‐fluorobenzyl)‐9‐azabicyclo[3.3.1]nonan‐3β‐yl]benzamide ([18F]MABN) and [18F]2,3‐dimethoxy‐N‐[1‐(4‐fluorobenzyl)piperidin‐4‐yl]benzamide ([18F]MBP). Studies were also conducted with the butyrophenone [18F]N‐methylspiperone (NMSP) for comparison. Tissue‐time activity curves of [18F]MABN are similar to those of [18F]NMSP since both compounds displayed approximately the same uptake in the basal ganglia and displayed irreversible binding kinetics in vivo. However, the rapid rate of clearance from the cerebellum and high basal ganglia: cerebellum ratio of [18F]MABN indicate that this compound has a much lower amount of nonspecific binding than [18F]NMSP. [18F]MBP displayed a higher uptake in the basal ganglia relative to [18F]NMSP and [18F]MABN and exhibited reversible binding kinetics in vivo. This property of [18F]MBP is desirable since the uptake of radioactivity in D2‐rich ligands is less likely to be influenced by changes in cerebral blood flow. The current data suggest that both [18F]MABN and [18F]MBP are promising ligands for studying dopamine D2 receptors with PET.Keywords
This publication has 53 references indexed in Scilit:
- Fluorine-18-labelled NCQ 115, a selective dopamine D-2 receptor ligand. Preparation and positron emission tomographyNuclear Medicine and Biology, 1994
- The use of [18F]4-fluorobenzyl iodide (FBI) in PET radiotracer synthesis: Model alkylation studies and its application in the design of dopamine D1 and D2 receptor-based imaging agentsNuclear Medicine and Biology, 1993
- 2- and 4-[18F]fluorotropapride, two specific D2 receptor ligands for positron emission tomography: N.C.A. syntheses and animal studiesInternational Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1992
- Neuroreceptor Quantitation in vivo by the Steady-State Principle Using Constant Infusion or Bolus Injection of Radioactive TracersJournal of Cerebral Blood Flow & Metabolism, 1992
- PET studies of dopamine receptor distribution using [18F]fluoroethylspiperone: findings in disorders related to the dopaminergic systemJournal Of Neural Transmission-Parkinsons Disease and Dementia Section, 1990
- Organization of dopamine D1 and D2 receptors in human striatum: Receptor autoradiographic studies in Huntington's disease and schizophreniaSynapse, 1988
- In vivo binding of 3H-N-methylspiperone to dopamine and serotonin receptorsLife Sciences, 1987
- []-N-: The radioligand of choice for pett studies of the dopamine receptor in human brainLife Sciences, 1985
- Assessment of dopamine receptor densities in the human brain with carbon-11-labeled N-methylspiperoneAnnals of Neurology, 1984
- Relationship between the inhibition constant (KI) and the concentration of inhibitor which causes 50 per cent inhibition (I50) of an enzymatic reactionBiochemical Pharmacology, 1973