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Updated: Aug 31, 2026

Comprehensive Profiling of Dopamine Regulation in Substantia Nigra and Ventral Tegmental Area
Published on: August 10, 2012
Phenylephrine and norepinephrine increase dopamine transporter ligand binding in striatum
Michael Byas-Smith1, John Votaw, Jian Hua
1Department of Anesthesiology, Emory University School of Medicine, Atlanta, Georgia 30022, USA. michael_byas-smith@emoryhealthcare.org
Purpose:
8-(2-[18F]fluoroethyl)-2 beta-carbomethoxy-3beta-(4-chlorophenyl)nortropane ([18F]FECNT) is a radiotracer for positron emission tomography (PET) used to trace the location and binding potential (BP) of the dopamine transporter (DAT). We tested the hypothesis that adrenergic receptor agonists increase the BP of [18F]FECNT for the DAT.
Procedures:
Anesthetized monkeys were scanned twice to determine the ligand BP at baseline and during administration of phenylephrine (3-6 microg/kg/min) or norepinephrine (0.5-1 microg/kg/min). Standard immunohistochemistry and immunoblot analyses were performed in rats to determine if the quantity of DAT changed with phenylephrine. [18F]FECNT uptake in human embryonic kidney (HEK) cells, stably transfected with DAT cDNA, was measured by gamma scintillation counting during phenylephrine.
Results:
The PET measured BP of [18F]FECNT increased by 50% and 45% during the phenylephrine and norepinephrine infusion, respectively. The immunohistochemistry and immunoblot analyses did not show a difference in total DAT.
Conclusion:
Adrenergic agonists increase the BP of [18F]FECNT in monkey striatum.
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