Comparative evaluations of norepinephrine transporter radioligands with reference tissue models in rhesus monkeys: (S,S)-[18F]FMeNER-D2 and (S,S)-[11C]MeNER.
OBJECTIVE
Although two norepinephrine transporter (NET) radioligands, (S,S)-[(18)F]FMeNER-D(2) and (S,S)-[(11)C]MeNER, have been reported to have different characteristics, there has not been a direct comparative study in vivo.


METHODS
In this preliminary study, two rhesus monkeys underwent three PET measurements each, one with (S,S)-[(18)F]FMeNER-D(2) and two with different radioactivity of (S,S)-[(11)C]MeNER (360 and 175 MBq). The regional brain uptakes and BP(ND) values from reference tissue models with different time lengths were compared.


RESULTS
The regional uptakes in the thalamus and the brainstem with (S,S)-[(11)C]MeNER did not always reach the peak during 123-min measurements while those with (S,S)-[(18)F]FMeNER-D(2) reached the peak before 30 min. The regional BP(ND) values of (S,S)-[(18)F]FMeNER-D(2) were stable after 150-min measurement lengths while those of (S,S)-[(11)C]MeNER were not stable during 123-min measurements.


CONCLUSIONS
(S,S)-[(18)F]FMeNER-D(2) appears to be superior for the quantitative analysis with reference tissue models in the rhesus monkey.
Takano
Akihiro
A
Department of Clinical Neuroscience, Psychiatry Section, Karolinska Institutet, 171 76 Stockholm, Sweden. Akihiro.Takano@ki.se
Gulyás
Balázs
B
Varrone
Andrea
A
Halldin
Christer
C
D000818:Animals; D001921:Brain / Q000166:cytology / Q000000981:diagnostic imaging / Q000378:metabolism; D005260:Female; D008024:Ligands; D008253:Macaca mulatta; D008954:Models, Biological; D009025:Morpholines / Q000378:metabolism*; D050484:Norepinephrine Plasma Membrane Transport Proteins / Q000378:metabolism*; D049268:Positron-Emission Tomography; D012016:Reference Values
C506462:2-(alpha-(2-fluoromethoxyphenoxy)benzyl)morpholine; C483610:2-(alpha-(2-methoxyphenoxy)benzyl)morpholine; D008024:Ligands; D009025:Morpholines; D050484:Norepinephrine Plasma Membrane Transport Proteins