Single photon emission computer tomography of dopamine transporters in monkeys and humans with 99mTc-TRODAT-1.
BACKGROUND
The diagnosis of Parkinson's disease is presently based on non-specific symptoms. However, radionuclide dopamine transporters imaging can provide specific diagnostic tool for Parkinson's disease. This study was designed to investigate the effects of imaging of dopamine transporters with 99mTc-TRODAT-1 in early diagnosis or differential diagnosis of Parkinson's disease.


METHODS
Nine normal monkeys were used to establish N-methyl-4-phenyl-1, 2, 3, 6-tetra-hydropyridine (MPTP) hemi-Parkinsonian animal models, and they were subjected to imaging. Twenty-nine patients with Parkinson's disease, 12 age-matched healthy volunteers, and 18 age-matched patients with Parkinson's syndrome were investigated. Single photon emission computer tomography (SPECT) was performed 3 hours after intravenous injection of 740 MBq 99mTc-TRODAT-1. Striatum specific uptake of 99mTc-TRODAT-1 was calculated according to the ratio of striatum (ST) to cerebellum (CB) in dopamine transporters uptake.


RESULTS
In normal monkeys, bilateral ratio of ST/CB was 2.34 +/- 0.41. After the injection of MPTP, uptake rate of 99mTc-TRODAT-1 at damaged region was much lower than that at the contralateral region, resulting in a significant difference in the ratio of ST/CB (right: ST/CB = 1.73 +/- 0.35; left: ST/CB = 1.90 +/- 0.30), especially in hemi-Parkinsonian model monkeys (right: ST/CB = 1.29 +/- 0.17; left: ST/CB = 1.80 +/- 0.33). The ratios of ST/CB were 1.57 +/- 0.17 and 1.61 +/- 0.14 for the right and left respectively in the healthy volunteers, 1.04 +/- 0.29 and 1.06 +/- 0.30 in the age-matched patients with Parkinson's disease, and 1.56 +/- 0.17 and 1.59 +/- 0.18 in the age-matched patients with Parkinson's disease syndrome. A significant difference was noted between group of Parkinson's disease, normal controls and Parkinson's disease syndrome.


CONCLUSIONS
The results suggest that 99mTc-TRODAT-1 dopamine transporters SPECT has clinical application value in early diagnosis or differential diagnosis of Parkinson's disease.
Hu
Ping
P
Department of Nuclear Medicine, First Affiliated Hospital, Sun Yat-sen University, Guangzhou 510080, China. hupinggz@163.net
Chen
Ling
L
Zhang
Hai-qin
HQ
Li
Jin-ru
JR
Liang
Hong
H
D000328:Adult; D000368:Aged; D000818:Animals; D050483:Dopamine Plasma Membrane Transport Proteins; D005260:Female; D000882:Haplorhini; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000032:analysis*; D026901:Membrane Transport Proteins / Q000032:analysis*; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000032:analysis*; D015609:Organotechnetium Compounds; D010300:Parkinson Disease / Q000175:diagnosis; D019275:Radiopharmaceuticals; D015899:Tomography, Emission-Computed, Single-Photon; D014326:Tropanes
D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; D014326:Tropanes; C104196:technetium Tc 99m TRODAT-1