Linked Life Data

20571518

Source:http://linkedlifedata.com/resource/pubmed/id/20571518

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2011-1-4
pubmed:abstractText
Positron emission tomography studies of 5-hydroxytryptamine (5-HT)(1A) receptors have hitherto been limited to antagonist radiotracers. Antagonists do not distinguish high/low-affinity conformations of G protein-coupled receptors and are less likely to be sensitive to intrasynaptic serotonin levels. We developed a novel 5-HT(1A) agonist radiotracer [(11)C]CUMI-101. This study evaluates the sensitivity of [(11)C]CUMI-101 binding to increases in intrasynaptic serotonin induced by intravenous citalopram and fenfluramine. Two Papio anubis were scanned, using [(11)C]CUMI-101 intravenous bolus of 4.5 ± 1.5 mCi. Binding potential (BP(F)=B(avail)/K(D)) was measured before (n=10) and 20 minutes after elevation of intrasynaptic serotonin by intravenous citalopram (2 mg/kg, n=3; 4 mg/kg, n=3) and fenfluramine (2.5 mg/kg, n=3) using a metabolite-corrected arterial input function. Occupancy was also estimated by the Lassen graphical approach. Both citalopram and fenfluramine effects were significant for BP(F) (P=0.031, P=0.049, respectively). The Lassen approach estimated 15.0, 30.4, and 23.7% average occupancy after citalopram 2 mg/kg, 4 mg/kg, and fenfluramine 2.5 mg/kg, respectively. [(11)C]CUMI-101 binding is sensitive to a large increase in intrasynaptic serotonin in response to robust pharmacological challenges. These modest changes in BP(F) may make it unlikely that this ligand will detect changes in intrasynaptic 5-HT under physiologic conditions; future work will focus on evaluating its utility in measuring the responsiveness of the 5-HT system to pharmacological challenges.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1559-7016
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
31
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
243-9
pubmed:dateRevised
2011-4-8
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
In vivo serotonin-sensitive binding of [11C]CUMI-101: a serotonin 1A receptor agonist positron emission tomography radiotracer.
pubmed:affiliation
Department of Psychiatry, Columbia University, College of Physicians and Surgeons, New York, New York 10032, USA. mm2354@columbia.edu
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural