Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2001-8-21
pubmed:abstractText
We have previously shown that beta-endorphin (END) is contained and released from memory-type T-cells within inflamed tissue and that it is capable to control pain (J Clin Invest 100(1) (1997) 142). Methionine-enkephalin (MET) and Dynorphin-A (DYN) are endogenous opioids with preference for delta- and kappa-opioid receptors, respectively. Both MET and DYN are produced and contained within immune cells. The goal of this study was to determine the release characteristics of MET and DYN in a rat model of localized hindpaw inflammation and to examine the antinociceptive role of MET and DYN in a Freund's adjuvant induced model of inflammatory pain. We found that corticotropin-releasing factor (CRF) can stimulate the release of both MET and DYN from lymphocytes. This release is dose-dependent and reversible by the selective CRF antagonist alpha-helical-CRF. Furthermore, CRF (1.5 ng) produces analgesia when injected into the inflamed paw, which is reversible by direct co-administration of antibodies to MET. Lymphocyte content of MET was 7.0+/-1.4 ng/million cells, whilst DYN content was ~30-fold lower. Both END and DYN, but not MET, were released by IL-1. Consistently, IL-1 produced peripheral analgesic effects which were not reversed by antibodies to MET. These results indicate that both MET and DYN play a role in peripheral analgesia but have different characteristics of release. These studies further support a role of the immune system in the control of inflammatory pain. This may be particularly important in patients suffering from compromised immune systems as with cancer and AIDS.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0304-3959
pubmed:author
pubmed:issnType
Print
pubmed:volume
93
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
207-12
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Methionine-enkephalin-and Dynorphin A-release from immune cells and control of inflammatory pain.
pubmed:affiliation
Behavioral Pharmacology and Genetics Section, Intramural Research Program, NIDA/NIH, Baltimore, MD 21224, USA. pcabot@pharmacy.uq.edu.au
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't