Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2007-5-21
pubmed:abstractText
Adenosine is a neuromodulator with complex effects on pain pathways. Mice lacking the adenosine A2A receptor are hypoalgesic, and have altered analgesic responses to receptor-selective opioid agonists. These and other findings suggest a role for the adenosine A2A receptor in sensitizing afferent fibres projecting to the spinal cord. To test this hypothesis formalin (20 microl, 5%) was injected into the paw and nociceptive responses were measured in wildtype and adenosine A2A receptor knockout mice. There was a significant reduction in nociception associated with sensory nerve activation in the knockout mice as measured by time spent biting/licking the formalin-injected paw and number of flinches seen during the first phase, but only the number of flinches was reduced during the second inflammatory phase. In addition, the selective adenosine A2A antagonist SCH58261 (3 and 10 mg/kg) also antagonised both phases of the formalin test. We also labelled NMDA glutamate and NK1 receptors in spinal cord sections as an indirect measure of nociceptive transmission from peripheral sites to the spinal cord. [3H]-Substance P binding to NK1 receptors was unaltered but there was a substantial reduction in binding of [3H]-MK801 to NMDA glutamate receptors in all regions of the spinal cord from knockout mice. The decrease in NMDA glutamate receptor binding may reflect reduced peripheral sensory input to the spinal cord during development and could relate to the hypoalgesia in this genotype. These results support a key role for the adenosine A2A receptor in peripheral nociceptive pathways.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1872-6623
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
129
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
287-94
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Reduced response to the formalin test and lowered spinal NMDA glutamate receptor binding in adenosine A2A receptor knockout mice.
pubmed:affiliation
School of Biomedical and Molecular Sciences, University of Surrey, Guildford GU2 7XH, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't