99mTc-TRODAT-1 Brain Spect Radiotracer
The radiotracer 99mTc-TRODAT-1, is a Technetium-99m labeled tropane derivative radioligand that binds to Dopamine Transporter (DAT). Tropane derivatives are alkaloids similar to atropine and cocaine, extracted from some plants. 99mTc-TRODAT-1 mediates the reuptake of free dopamine from the intrasynaptic cleft and can be used to image the dopaminergic system. The concentration of dopamine transporters reflects the activity of the dopaminergic system. Technetium-99m has a half life of 6 h and is easily obtained from a 99Mo Generator. To perform the procedure, a single bolus dose of 740 MBq (20 mCi) of 99mTc-TRODAT-1 is injected intravenously. Patient may complain of a mild and transient burning sensation at the site of injection if ethanol is used to dissolve the radiotracer. The quantity of compound present in the vial is less than 1 mg, so no pharmacologic effects are produced. See below radiation doses, package insert and radiotracer labeling.
Radiation Doses Pakage Insert Radiotracer labeling
References:
1 Chou K.L., Hurtig, HI., Stern, M.B., Colcher, A., Ravina,B., Newberg A., Mozley P.D., Siderowf, A.. Diagnostic accuracy of [99mTc]TRODAT-1 SPECT imaging in early Parkinson’s disease. Parkinsonism and Related Disorders 10 (2004) 375–379.
2 Andre C. Felicio, Clecio Godeiro-Junior, Ming C. Shih, Vanderci Borges, Sônia M.A. Silva, Patrícia de Carvalho Aguiar, Marcelo Q. Hoexter, Orlando G.P. Barsottini, Luiz A.F. Andrade, Rodrigo A. Bressan, Henrique B. Ferraz. Evaluation of patients with Clinically Unclear Parkinsonian Syndromes submitted to brain SPECT imaging using the technetium-99m labeled tracer TRODAT-1. Journal of the Neurological Sciences 2010; 291: 64–68.