[11C]-(+)-PHNO (4-propyl-9-hydroxynaphthoxazine) is a new agonist radioligand that provides a unique opportunity to measure the high-affinity states of the D2 receptors (D2-high) using positron emission tomography (PET). Here we report on the distribution, displaceablity, specificity and modeling of [11C]-(+)-PHNO and compare it with the well characterized antagonist D2 radioligand, [11C]raclop...

4-Acetoxy derivative (1) of L-703,717, a high-affinity (IC50=4.5 nM) antagonist for the glycine site of NMDA receptors, was synthesized and its brain uptake was examined using a carbon-11 labeled analog ([11C]1). Initial radioactivity in the brain after intravenous injection of [11C]1 was a 2-fold that of [11C]L-703,717 in mice. Rapid bioconversion of [11C]1 into [11C]L-703,717 was demonstrated...

In previous in vivo studies with mice, rats, cats and monkeys, we have demonstrated that [7-methyl-11C]-(E)-8-(3,4,5-trimethoxystyryl)- 1,3,7-trimethylxanthine ([11C]TMSX) is a potential radioligand for mapping adenosine A2A receptors of the brain by positron emission tomography (PET). In the present study, we studied the potential of [11C]TMSX for myocardial imaging. Uptake of radioactivity by...

Carbon-11-labeled SarCNU [N-(2-chloroethyl)-N-nitroso-N'-(carboxamidomethylene)-N'-(methyl) - [11C]-urea], a potential chemotherapeutic agent, has been prepared by the nitrosation of the corresponding urea, N-(2-chloroethyl)-N'-(carboxamidomethylene)-N'-(methyl) [11C]urea (SarCU). SarCU was prepared by reacting sarcosinamide with [11C]-2-chloroethylisocyanate, which was itself prepared by react...

I investigated the differences in brain pharmacokinetics of [11C]methamphetamine ([11C]MAP) in normal and MAP sensitized animals using positron emission tomography (PET). [11C]MAP was synthesized by an automated on-line [11C]methylation system. I newly produced MAP sensitized dog and monkey by repeated MAP treatment. The maximal level of accumulation of [11C]MAP in the sensitized dog brain was ...

The present study evaluated short- and long-term effects of MDMA (3,4-methylenedioxymethamphetamine) in the baboon brain using PET and [11C](+)McN 5652, a potent 5-HT transporter ligand, as well as [11C]RTI-55, a cocaine derivative which labels both 5-HT and dopamine transporters. Following baseline PET scans with [11C](+)McN5652, [11C](-)McN5652 (the inactive enantiomer of the active enantiome...

objective(s): it is difficult to investigate the whole-body distribution of an orally administered drug by means of positron emission tomography (pet), owing to the short physical half-life of radionuclides, especially when 11c-labeled compounds are tested. therefore, we aimed to examine the whole-body distribution of donepezil (dnp) as an acetylcholinesterase inhibitor by means of 11c-dnp pet ...

IMPORTANCE Neuroinflammation may play a role in epilepsy. Translocator protein 18 kDa (TSPO), a biomarker of neuroinflammation, is overexpressed on activated microglia and reactive astrocytes. A preliminary positron emission tomographic (PET) imaging study using carbon 11 ([11C])-labeled PBR28 in patients with temporal lobe epilepsy (TLE) found increased TSPO ipsilateral to seizure foci. Full q...

A novel amide synthesis methodology is described using amines, CO2 and Grignard reagents and Mitsunobu reagents. The method was applied to carbon-11 radiochemistry to label amides using cyclotron-produced [11C]CO2. The synthetic utility of the one-pot labelling methodology was demonstrated by producing [11C]melatonin. The incorporation of [11C]CO2 into [11C]melatonin was 36% - determined by rad...

BACKGROUND [11C]Flumazenil and positron emission tomography (PET) are used clinically to assess gamma-aminobutyric acid (GABA)-ergic function and to localize epileptic foci prior to resective surgery. Enhanced P-glycoprotein (P-gp) activity has been reported in epilepsy and this may confound interpretation of clinical scans if [11C]flumazenil is a P-gp substrate. The purpose of this study was t...