Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1999-6-3
pubmed:abstractText
[99mTc]TRODAT-1 was the first 99mTc-labeled imaging agent to show specific binding to dopamine transporters (DAT) in the striatum (STR) of human brain. Additionally, in vitro binding and autoradiographic experiments demonstrated that this tracer also binds to serotonin transporters (SERT) in the midbrain/hypothalamus (MB) area. In this study, [99mTc]TRODAT-1 was investigated as a potentially useful ligand to image SERT in the MB of living brain. A total of eight single-photon emission tomography (SPET) scans were performed in two baboons (Papio anubis) after intravenous (i.v.) injection of 740 MBq (20 mCi) of [99mTc]TRODAT-1 using a triple-head gamma camera equipped with ultra-high-resolution fan-beam collimators (scan time: 0-210 min). In four blocking studies, baboons were pretreated with (+)McN5652 (1 mg/kg, i.v.) or methylphenidate (1 mg/kg, i.v.) to specifically block SERT or DAT, respectively. After co-registration with magnetic resonance images of the same baboon, a region of interest analysis was performed using predefined templates to calculate specific uptake in the midbrain area and the striatum, with the cerebellum as the background region [(MB-CB)/CB, (STR-CB)/CB]. Additionally, two PET scans of the same baboons were performed after i.v. injections of 74-111 MBq (2-3 mCi) of [11C](+)McN5652 to identify the SERT sites. In [99mTc]TRODAT-1/SPET scans, the SERT sites in the MB region were clearly visualized. Semiquantitative analysis revealed a specific uptake in MB ([MB-CB]/CB) of 0.30+/-0.02, which was decreased to 0. 040+/-0.005 after pretreatment with nonradioactive (+)McN5652, a selective SERT ligand. Pretreatment with methylphenidate reduced the specific binding of [99mTc]TRODAT-1 to DAT sites [(STR-CB)/CB] from 2.45+/-0.13 to 0.32+/-0.04 without any effect on its binding to SERT sites [(MB-CB)/CB], which was confirmed by the co-registration of the [11C](+)McN5652/PET scans. This preliminary study suggests that specific binding of [99mTc]TRODAT-1 to SERT sites can be detected by in vivo SPET imaging despite the low target to background ratio. These findings provide impetus for further development of similar compounds with improved binding affinity and selectivity to SERT sites.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Adrenergic Uptake Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Carrier Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Isoquinolines, http://linkedlifedata.com/resource/pubmed/chemical/McN 5652, http://linkedlifedata.com/resource/pubmed/chemical/Membrane Glycoproteins, http://linkedlifedata.com/resource/pubmed/chemical/Membrane Transport Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Methylphenidate, http://linkedlifedata.com/resource/pubmed/chemical/Nerve Tissue Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Organotechnetium Compounds, http://linkedlifedata.com/resource/pubmed/chemical/Radiopharmaceuticals, http://linkedlifedata.com/resource/pubmed/chemical/Serotonin Antagonists, http://linkedlifedata.com/resource/pubmed/chemical/Serotonin Plasma Membrane..., http://linkedlifedata.com/resource/pubmed/chemical/Tropanes, http://linkedlifedata.com/resource/pubmed/chemical/technetium Tc 99m TRODAT-1
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0340-6997
pubmed:author
pubmed:issnType
Print
pubmed:volume
26
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
342-7
pubmed:dateRevised
2005-11-17
pubmed:meshHeading
pubmed-meshheading:10199939-Adrenergic Uptake Inhibitors, pubmed-meshheading:10199939-Animals, pubmed-meshheading:10199939-Brain, pubmed-meshheading:10199939-Carrier Proteins, pubmed-meshheading:10199939-Female, pubmed-meshheading:10199939-Image Processing, Computer-Assisted, pubmed-meshheading:10199939-Isoquinolines, pubmed-meshheading:10199939-Membrane Glycoproteins, pubmed-meshheading:10199939-Membrane Transport Proteins, pubmed-meshheading:10199939-Methylphenidate, pubmed-meshheading:10199939-Nerve Tissue Proteins, pubmed-meshheading:10199939-Organotechnetium Compounds, pubmed-meshheading:10199939-Papio, pubmed-meshheading:10199939-Radiopharmaceuticals, pubmed-meshheading:10199939-Serotonin Antagonists, pubmed-meshheading:10199939-Serotonin Plasma Membrane Transport Proteins, pubmed-meshheading:10199939-Tissue Distribution, pubmed-meshheading:10199939-Tomography, Emission-Computed, pubmed-meshheading:10199939-Tomography, Emission-Computed, Single-Photon, pubmed-meshheading:10199939-Tropanes
pubmed:year
1999
pubmed:articleTitle
In vivo imaging of serotonin transporters with [99mTc]TRODAT-1 in nonhuman primates.
pubmed:affiliation
Department of Radiology, University of Pennsylvania, Philadelphia 19104, USA.
pubmed:publicationType
Journal Article