Linked Life Data

9833011

Source:http://linkedlifedata.com/resource/pubmed/id/9833011

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-3
pubmed:dateCreated
1998-12-29
pubmed:abstractText
The purpose of the present investigation was to examine the discriminative stimulus effects of opioids with activity at mu and kappa opioid receptors, in pigeons trained to discriminate the mu opioid fentanyl, the kappa opioid bremazocine and water in a three-choice discrimination task. The apparent pkB values obtained for naloxone as an antagonist of the stimulus effects of fentanyl were higher than those obtained against the bremazocine stimulus. The mu opioids morphine and l-methadone substituted for the fentanyl stimulus, the kappa opioids U50,488 and U69,593 substituted for the bremazocine stimulus, and the non-opioid pentobarbital failed to substitute for either the fentanyl or bremazocine stimulus. A series of opioids with activity at both the mu and kappa opioid receptor sites, including nalorphine, butorphanol, buprenorphine, nalbuphine, ethylketocyclazocine, (-)-ketocyclazocine, (-)-n-allylnormetazocine (NANM) and levallorphan, produced high levels of substitution for the fentanyl stimulus without producing appreciable levels of substitution for the bremazocine stimulus. At doses that did not substitute for the fentanyl stimulus, (-)-NANM, levallorphan, nalorphine and nalbuphine partially antagonized the bremazocine stimulus (i.e. produced responding on the water key). Butorphanol and buprenorphine also antagonized the bremazocine stimulus, although this effect was evidenced only at doses that substituted for the fentanyl stimulus. In contrast, even when tested up to doses that markedly decreased rates of responding, ethylketocyclazocine and (-)-ketocyclazocine failed to antagonize the bremazocine stimulus. The present findings indicate that in this three-choice task the fentanyl-like substitution patterns produced by opioids with activity at both the mu and kappa opioid receptors are similar to those reported in pigeons trained to discriminate either fentanyl or bremazocine from saline (i.e. two-choice tasks). In this task, however, the level of kappa antagonist activity evidenced by these opioids was considerably less than that obtained in pigeons trained to discriminate bremazocine from saline.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0955-8810
pubmed:author
pubmed:issnType
Print
pubmed:volume
8
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
160-73
pubmed:dateRevised
2009-7-7
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Discriminative stimulus effects of opioids in pigeons trained to discriminate fentanyl, bremazocine and water: evidence of pharmacological selectivity.
pubmed:affiliation
Department of Psychology, University of North Carolina at Chapel Hill 27599-3270, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.