Simultaneous [99mTc]TRODAT-1 and [123I]ADAM brain SPECT in nonhuman primates.
OBJECTIVE
This study examined the feasibility of simultaneous dopamine and serotonin transporter imaging using [(123)I]ADAM and [(99m)Tc]TRODAT-1 single photon emission computed tomography (SPECT).


METHODS
Simultaneous [(123)I]ADAM (185 MBq) and [(99m)Tc]TRODAT-1 (740 MBq) SPECT was performed in three age-matched female Formosan rock monkeys. An asymmetric energy window was used for dual, and symmetric energy windows were used for single-isotope imaging. Oral fluoxetine (20 mg) and intravenous methylphenidate HCl (1 mg/kg) were given 24 h and 10 min, respectively, before dual-isotope SPECT to test imaging specificities of [(123)I]ADAM and [(99m)Tc]TRODAT-1.


RESULTS
Comparable image quality and uptake ratios between dual- and single-isotope SPECT scans were found. Dual-isotope SPECT in fluoxetine-pretreated monkeys showed decreased uptake of [(123)I]-ADAM, but not of [(99m)Tc]TRODAT-1. Dual-isotope SPECT in methylphenidate-pretreated monkeys showed decreased [(99m)Tc]TRODAT-1 uptake without affecting [(123)I]-ADAM uptake.


CONCLUSIONS
Simultaneous [(123)I]-ADAM and [(99m)Tc]TRODAT-1 SPECT appears promising in nonhuman primates and may provide a suitable preclinical model with further clinical implications.
Ma
Kuo-Hsing
KH
Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan.
Lee
Jong-Kang
JK
Huang
San-Yuan
SY
Yeh
Chin-Bin
CB
Shen
Yi-Chun
YC
Shen
Lie-Hang
LH
Chen
Chia-Chieh
CC
Liu
Ren-Shyan
RS
Liu
Jiang-Chuan
JC
Huang
Wen-Sheng
WS
D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism*; D002928:Cinanserin / Q000031:analogs & derivatives* / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism*; D005260:Female; D005473:Fluoxetine / Q000494:pharmacology; D000882:Haplorhini; D007091:Image Processing, Computer-Assisted; D008774:Methylphenidate / Q000494:pharmacology; D015609:Organotechnetium Compounds / Q000378:metabolism*; D019275:Radiopharmaceuticals / Q000378:metabolism; D050486:Serotonin Plasma Membrane Transport Proteins / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014326:Tropanes / Q000378:metabolism*
C413491:2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine; D050483:Dopamine Plasma Membrane Transport Proteins; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D050486:Serotonin Plasma Membrane Transport Proteins; D014326:Tropanes; C104196:technetium Tc 99m TRODAT-1; D005473:Fluoxetine; D008774:Methylphenidate; D002928:Cinanserin; D004298:Dopamine