Linked Life Data

9778190

Source:http://linkedlifedata.com/resource/pubmed/id/9778190

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1998-11-9
pubmed:abstractText
[18F]Fluoropropyl-TZTP (FP-TZTP) is a subtype-selective muscarinic cholinergic ligand with potential suitability for studying Alzheimer's disease. Positron emission tomography studies in isofluorane-anesthetized rhesus monkeys were performed to assess the in vivo behavior of this radiotracer. First, control studies (n = 11) were performed to characterize the tracer kinetics and to choose an appropriate model using a metabolite-corrected arterial input function. Second, preblocking studies (n = 4) with unlabeled FP-TZTP were used to measure nonspecific binding. Third, the sensitivity of [18F]FP-TZTP binding to changes in brain acetylcholine (ACh) was assessed by administering physostigmine, an acetylcholinesterase (AChE) inhibitor, by intravenous infusion (100 to 200 microg x kg(-1) x h(-1)) beginning 30 minutes before tracer injection (n = 7). Tracer uptake in the brain was rapid with K1 values of 0.4 to 0.6 mL x min(-1) x mL(-1) in gray matter. A model with one tissue compartment was chosen because reliable parameter estimates could not be obtained with a more complex model. Volume of distribution (V) values, determined from functional images created by pixel-by-pixel fitting, were very similar in cortical regions, basal ganglia, and thalamus, but significantly lower (P < 0.01) in the cerebellum, consistent with the distribution of M2 cholinergic receptors. Preblocking studies with unlabeled FP-TZTP reduced V by 60% to 70% in cortical and subcortical regions. Physostigmine produced a 35% reduction in cortical specific binding (P < 0.05), consistent with increased ACh competition. The reduction in basal ganglia (12%) was significantly smaller (P < 0.05), consistent with its markedly higher AChE activity. These studies indicate that [18F]FP-TZTP should be useful for the in vivo measurement of muscarinic receptors with positron emission tomography.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0271-678X
pubmed:author
pubmed:issnType
Print
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1130-42
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed-meshheading:9778190-Acetylcholine, pubmed-meshheading:9778190-Anesthesia, pubmed-meshheading:9778190-Anesthetics, Inhalation, pubmed-meshheading:9778190-Animals, pubmed-meshheading:9778190-Binding, Competitive, pubmed-meshheading:9778190-Blood Proteins, pubmed-meshheading:9778190-Brain, pubmed-meshheading:9778190-Cholinesterase Inhibitors, pubmed-meshheading:9778190-Chromatography, Thin Layer, pubmed-meshheading:9778190-Fluorine Radioisotopes, pubmed-meshheading:9778190-Isoflurane, pubmed-meshheading:9778190-Kinetics, pubmed-meshheading:9778190-Macaca mulatta, pubmed-meshheading:9778190-Models, Neurological, pubmed-meshheading:9778190-Physostigmine, pubmed-meshheading:9778190-Pyridines, pubmed-meshheading:9778190-Receptors, Muscarinic, pubmed-meshheading:9778190-Thiazoles, pubmed-meshheading:9778190-Tomography, Emission-Computed
pubmed:year
1998
pubmed:articleTitle
Muscarinic cholinergic receptor measurements with [18F]FP-TZTP: control and competition studies.
pubmed:affiliation
Positron Emission Tomography Department, National Institutes of Health, Bethesda, Maryland 20892-1180, USA.
pubmed:publicationType
Journal Article