Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2008-10-28
pubmed:abstractText
1. Receptor transport between intracellular compartments has important consequences for receptor function and is an exciting area of current study. Existing methods for studying receptor trafficking often require labour-intensive techniques or are difficult to quantify reliably. We report a novel high-throughput method that uses automated imaging and analysis tools to accurately quantify cannabinoid CB1 receptor trafficking. 2. Haemagglutinin (HA)-tagged CB1 was stably expressed in HEK-293 cells and cell surface or total receptors were detected immunocytochemically. Images of receptor and nuclear staining were acquired with an automated fluorescent microscope (Discovery-1; Molecular Devices, Sunnyvale, CA, USA) and quantified at high throughput with MetaMorph (Molecular Devices) software. The 'Granularity' assay measured internalization by counting receptor clusters that appear during receptor endocytosis, a well-established approach. Our assay, referred to as 'Total Grey Value per Cell' (TGVC), measures the total fluorescence above background, normalized to cell count. 3. Incubation with the cannabinoid agonist HU-210 (100 nmol/L) resulted in rapid CB1 internalization, reaching a maximum within 20 min. Whether quantified by Granularity or TGVC, the time-course of endocytosis could be modelled with exponentially derived curves and with similar half-lives. We demonstrate the sensitivity of our TGVC method by measuring the concentration dependence of CB1 internalization and its versatility by measuring downregulation following chronic agonist exposure, whereby total CB1 was reduced to approximately 55% of basal after 3 h. 4. The TGVC quantification method described is efficient, accurate and versatile and is likely to provide a valuable tool in receptor trafficking studies.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1440-1681
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1377-82
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
A novel high-throughput assay for the quantitative assessment of receptor trafficking.
pubmed:affiliation
Department of Pharmacology, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't