Whole-body biodistribution, radiation dosimetry estimates for the PET norepinephrine transporter probe (S,S)-[18F]FMeNER-D2 in non-human primates.
BACKGROUND
(S,S)-[F]FMeNER-D2 is a recently developed norepinephrine transporter ligand which is a potentially useful radiotracer for mapping the brain and heart norepinephrine transporter in vivo using positron emission tomography. In this work, we quantified the biodistribution over time and radiation exposure to multiple organs with (S,S)-[F]FMeNER-D2.


METHODS
Whole-body images were acquired for 21 time points in two cynomolgus monkeys for approximately 270 min after injection of radioligand. Compressed 3-D to 2-D planar images were used to identify organs with the highest radiation exposure at each time point. Estimates of the absorbed dose of radiation were calculated using the MIRDOSE 3.1 software program performed with the dynamic bladder and ICRP 30 gastrointestinal tract models.


RESULTS
In planar images, peak values of the percent injected dose (%ID) at a time after radioligand injection were calculated for the lungs (26.76% ID at 1.42 min), kidneys (13.55% ID at 2.18 min), whole brain (5.65% ID at 4.48 min), liver (7.20% ID at 2 min), red bone marrow (5.02% ID at 2.06 min), heart (2.36% ID at 1.42 min) and urinary bladder (23% ID at 250 min). Assuming a urine voiding interval of 2.4 h, the four organs with highest exposures in microGy . MBq ( mrad . mCi) were kidneys 126 (468), heart wall 108 (399), lungs 88.4 (327) and urinary bladder 114 (422). The effective doses were estimated with and without urine voiding at a range of 123 (33) and to 131 (35.5) microGy . MBq ( mrad . mCi).


CONCLUSIONS
The estimated radiation burden of (S,S)-[F]FMeNER-D2 is comparable to that of other F radioligands.
Karolinska Institutet, Department of Clinical Neuroscience, Karolinska Hospital, Stockholm, Sweden. Nick.Seneca@cns.ki.se
Nicholas
N
Seneca
Bengt
B
Andree
Nils
N
Sjoholm
Magnus
M
Schou
Stefan
S
Pauli
P David
PD
Mozley
James B
JB
Stubbs
Jeih-San
JS
Liow
Judit
J
Sovago
Balazs
B
Gulyás
Robert
R
Innis
Christer
C
Halldin
D000818:Animals; D001822:Body Burden; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism*; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D008252:Macaca fascicularis; D008657:Metabolic Clearance Rate; D015336:Molecular Probe Techniques; D009025:Morpholines / Q000008:administration & dosage / Q000493:pharmacokinetics*; D009928:Organ Specificity; D049268:Positron-Emission Tomography / Q000379:methods*; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*; D019275:Radiopharmaceuticals / Q000008:administration & dosage / Q000493:pharmacokinetics; D012062:Relative Biological Effectiveness; D014018:Tissue Distribution; D014915:Whole-Body Counting
C506462:2-(alpha-(2-fluoromethoxyphenoxy)benzyl)morpholine; D009025:Morpholines; D019275:Radiopharmaceuticals