Linked Life Data

3208100

Source:http://linkedlifedata.com/resource/pubmed/id/3208100

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-2-22
pubmed:abstractText
Snake venom kappa-neurotoxins are selective antagonists of nicotinic acetylcholine responses in avian, murine and bovine neurons, and have been used as probes for functionally defined vertebrate neuronal nicotinic receptors. The actions of kappa-bungarotoxin, a kappa-neurotoxin, have now been examined at a central invertebrate nicotinic receptor. kappa-Bungarotoxin is a potent antagonist (IC50 = 100 nM) of nicotinic responses, producing a long-lasting blockade of insect nicotinic acetylcholine receptors. The blockade appears to be competitive, and voltage-clamp experiments on an identified cockroach motorneuron indicate that the actions of kappa-bungarotoxin are not dependent on membrane potential. alpha-Bungarotoxin is also a potent antagonist at the cockroach central nicotinic receptor, and binds (Kd = 4.3 nM) to a nicotinic site in cockroach nervous tissue. kappa-Bungarotoxin recognizes this invertebrate nicotinic site with high affinity (Ki = 27 nM). A comparison of the pharmacological properties of insect nicotinic receptors with those of functionally defined receptors identified by kappa-neurotoxins in avian autonomic ganglia reveals several similarities. However, a striking exception is alpha-bungarotoxin, which is the most potent antagonist examined at cockroach nicotinic receptors, but fails to recognize functional autonomic ganglia nicotinic receptors even at very high concentrations. It is concluded that kappa-neurotoxins can be used as selective probes for neuronal nicotinic receptors in both vertebrates and invertebrates. Although invertebrates diverged from vertebrates over 600 million years ago, the results indicate that the neuronal nicotinic receptors found in species as diverse as cockroach and chick retain considerable structural similarity, and thus neuronal nicotinic receptors appear to be highly conserved membrane proteins.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-8993
pubmed:author
pubmed:issnType
Print
pubmed:day
16
pubmed:volume
458
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
45-52
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Kappa-bungarotoxin blocks an alpha-bungarotoxin-sensitive nicotinic receptor in the insect central nervous system.
pubmed:affiliation
Department of Zoology, University of Cambridge, U.K.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.