Linked Life Data

15936681

Source:http://linkedlifedata.com/resource/pubmed/id/15936681

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2005-6-6
pubmed:abstractText
The mu opioid receptor may constitute a critical component of a negative feedback system that regulates Pavlovian fear conditioning. We investigated context fear conditioning acquisition and expression in mu opioid receptor knockout mice (on an inbred, C57 genetic background). We discovered that the mu receptor knockout results in an unexpected and significant deficit in context fear acquisition. Mice lacking the mu receptor showed normal fear acquisition when subjected to a 1-day fear conditioning protocol but evinced deficient fear learning when acquisition was conducted across 5 days. The knockout mice showed normal reactivity to footshock in both fear conditioning protocols. Finally, we confirmed the effectiveness of the receptor deletion in the C57 strain by subjecting the mice to a test of morphine analgesia in the hot-plate assay. As has been seen with mixed genetic background, the receptor deletion resulted in a complete lack of analgesic response to 10 mg/kg morphine. Surprisingly, mice with a single copy of the mu receptor gene (heterozygous knockouts) showed intact sensitivity to morphine but a significant deficit in Pavlovian fear conditioning. The results indicate that deletion of the mu receptor gene impairs fear conditioning and that the conditioning and analgesia effects of heterozygous deletion are dissociable. The conditioning deficit seen in this line of mice may be related to impairment in hippocampus function.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1074-7427
pubmed:author
pubmed:issnType
Print
pubmed:volume
84
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
33-41
pubmed:dateRevised
2007-10-17
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Deletion of the mu opioid receptor results in impaired acquisition of Pavlovian context fear.
pubmed:affiliation
UCLA Psychology Department, Los Angeles, CA, USA. msanders@psych.ucla.edu
pubmed:publicationType
Journal Article, Comparative Study, Validation Studies