Linked Life Data

10779374

Source:http://linkedlifedata.com/resource/pubmed/id/10779374

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2000-5-25
pubmed:abstractText
alpha-Conotoxin MII (CtxMII), a peptide toxin from the venom of the predatory cone snail Conus magus, displays an unusual nicotinic pharmacology. Specific binding of a radioiodinated derivative ((125)I-alpha-CtxMII) was identified in brain region homogenates and tissue sections. Quantitative autoradiography indicated that (125)I-alpha-CtxMII binding sites have an unique pharmacological profile and distribution in mouse brain, being largely confined to the superficial layers of the superior colliculus, nigrostriatal pathway, optic tract, olivary pretectal, and mediolateral and dorsolateral geniculate nuclei. Expression of alpha-CtxMII binding sites in the nigrostriatal pathway, combined with evidence for alpha-CtxMII-sensitivity of nicotine-induced [(3)H]dopamine release in rodent striatal preparations indicates that (125)I-alpha-CtxMII binding nicotinic acetylcholine receptors are likely to be physiologically important. Unlabeled alpha-CtxMII potently (K(i) < 3 nM) competed for a subset of [(3)H]epibatidine binding sites in mouse brain homogenates, but weakly (IC(50) > 10 microM) interacted with (125)I-alpha-bungarotoxin and (-)-[(3)H]nicotine binding sites, confirming this compound's novel nicotinic pharmacology. Quantitative autoradiography revealed that alpha-CtxMII binds with high affinity at a subset of [(3)H]epibatidine binding sites with relatively low cytisine affinity ("cytisine-resistant" sites), resolving [(3)H]epibatidine binding into three different populations, each probably corresponding to a receptor subtype. The majority population seems to correspond to that which binds nicotine and cytisine with high affinity ("cytisine-sensitive" sites). Comparison of the cytisine-resistant population's distribution with that of alpha3 subunit mRNA expression suggests that the fractions both more and less sensitive to alpha-CtxMII probably contain the alpha3 subunit, perhaps in combination with different beta subunits.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0026-895X
pubmed:author
pubmed:issnType
Print
pubmed:volume
57
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
913-25
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
125I-alpha-conotoxin MII identifies a novel nicotinic acetylcholine receptor population in mouse brain.
pubmed:affiliation
Institute for Behavioral Genetics, University of Colorado, Boulder, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.