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5
5. Stahl SM. Mechanism of action of trazodone: a multifunctional
drug. CNS Spectr. 2009;14(10):536‐546.
(Siemens AG, Munich, Germany), where scanning started
at the time of injection (0 minutes). Ninety minutes after
the injection of [18F]Cimbi‐92, ketanserin was given iv
as a within‐scan challenge bolus (5.0 mg/kg). Ketanserin
was dissolved in 3‐mL DMSO and subsequently diluted
with saline to a 10% DMSO solution. Radiochemical
purity and specific activity of the injected product were
measured with HPLC.
6. Herth MM, Knudsen GM. Current radiosynthesis strategies for
5‐HT2A receptor PET tracers. J Labelled Comp Radiopharm.
2015;58(7):265‐273.
7. Mühlhausen U, Ermert J, Herth MM, Coenen HH. Synthesis,
radiofluorination and first evaluation of ( )‐[18F]MDL‐100907
as serotonin 5‐HT2A receptor antagonist for PET. J Labelled
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4.7 | PET quantification and modelling
List‐mode PET data (150 minutes) were reconstructed into
58 dynamic frames of increasing length (6 × 10, 6 × 20,
6 × 30, 6 × 60, 4 × 120, 14× 300, 8 × 150, and 8 × 300 -
seconds). Images consisted of 207 planes of 256 × 256
voxels of 1.22 × 1.22 × 1.22 mm. A summed picture of all
counts in the 90‐minute scan was reconstructed for each
pig and used for co‐registration to a standardised MRI‐
based atlas of the Danish Landrace pig brain, similar to
that previously published.38,39 The time‐activity curves
(TACs) were calculated for the following volumes of
interest (VOIs): cerebellum, cortex, hippocampus, lateral
and medial thalamus, caudate nucleus, and putamen.
Striatum is defined as the mean radioactivity in caudate
nucleus and putamen. The activity in thalamus is
calculated as the mean radioactivity in the lateral and
medial thalamus. Radioactivity in all VOIs was calculated
as the average of radioactive concentration (Bq/mL) in the
left and right sides. Outcome measure in the time‐activity
curves (TACs) was calculated as radioactive concentration
in VOI (in kBq/mL) normalised to the injected dose
corrected for animal weight (in kBq/kg), yielding
standardised uptake values (g/mL).
9. Miller PW, Long NJ, Vilar R, Gee AD. Synthesis of 11C, 18F,
15O, and 13N radiolabels for positron emission tomography.
Angew Chem Int Ed Engl. 2008;47(47):8998‐9033.
10. Herth MM, Leth‐Petersen S, Lehel S, et al. Accelerating preclin-
ical PET‐screening: reductive amination with [C‐11]
methoxybenzaldehydes. RSC Adv. 2014;4(41):21347‐21350.
11. Herth MM, Debus F, Piel M, et al. Total synthesis and evaluation
of [18F]MHMZ. Bioorg Med Chem Lett. 2008;18(4):1515‐1519.
12. Debus F, Herth MM, Piel M, et al. 18F‐labeling and evaluation of
novel MDL 100907 derivatives as potential 5‐HT2A antagonists
for molecular imaging. Nucl Med Biol. 2010;37(4):487‐495.
13. Herth MM, Petersen IN, Hansen HD, et al. Synthesis and
evaluation of 18F‐labeled 5‐HT2A receptor agonists as PET
ligands. Nucl Med Biol. 2016;43(8):455‐462.
14. Petersen IN, Villadsen J, Hansen HD, et al. Convergent 18F‐
labeling and evaluation of N‐benzyl‐phenethylamines as 5‐
HT2A receptor PET ligands. Bioorg Med Chem.
2016;24(21):5353‐5356.
15. Herth MM, Kramer V, Gillings N, Rösch F, Knudsen GM. Direct
radiofluorination of [18F]MH.MZ for 5‐HT2A receptor molecu-
lar imaging with PET. J. Labelled. Comp. Radiopharm.
2012;55(9):354‐358.
16. Pehek EA, McFarlane HG, Maguschak K, Price B, Pluto CP.
M100,907, a selective 5‐HT(2A) antagonist, attenuates dopamine
release in the rat medial prefrontal cortex. Brain Res.
2001;888(1):51‐59.
ORCID
17. Kristiansen H, Elfving B, Plenge P, Pinborg LH, Gillings N,
Knudsen GM. Binding characteristics of the 5‐HT2A receptor
antagonists Altanserin and MDL 100907. Synapse.
2005;58(4):249‐257.
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