Linked Life Data

2158554

Source:http://linkedlifedata.com/resource/pubmed/id/2158554

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-5-30
pubmed:abstractText
The effect of continuous intrathecal infusions of opioids was studied in rats. Chronic intrathecal infusion of the highly selective mu agonist, [NMPhe3, D-Pro4]morphiceptin produced a rapid onset of tolerance to the drug in the analgesic test. However, membrane prepared from the spinal cords of the rats chronically infused with a low dose of the drug showed no statistically significant change in the number of mu or delta receptor binding sites. In addition, membrane prepared from rats challenged with a single high-dose bolus injection of [NMPhe3, D-Pro4]morphiceptin did not produce alterations in the receptor binding number. If the chronically treated rats were challenged with an acute bolus dose of [NMPhe3, D-Pro4]morphiceptin, there was a significant decrease in the number of binding sites. The reduced binding site number was observed for the mu ligand but not for the delta ligand. A similar decrease of receptor binding can also be achieved by chronic infusion of the drug at high doses. Scatchard plot showed a decrease of maximum mu binding sites in the membranes prepared from the combined chronic infusion-acute injection treated rats. Brain tissue from the same rats showed no change in the number of mu and delta receptor binding sites, indicating that the down-regulation of mu receptors was confined to the spinal cord only. Morphine did not induce receptor down-regulation by acute, chronic or combined treatments. These results suggest that in the rat spinal cord, tolerance can be induced without apparent receptor down-regulation.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-3565
pubmed:author
pubmed:issnType
Print
pubmed:volume
253
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
67-72
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Dissociation of mu opioid tolerance from receptor down-regulation in rat spinal cord.
pubmed:affiliation
Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.