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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3
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pubmed:dateCreated |
1997-1-7
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pubmed:abstractText |
We synthesized a potent and selective antagonist radioligand for the neurokinin (NK)-1 receptor and characterized its binding to guinea pig striatal membranes. (R)-N-[2-[Acetyl[3H3][(2-methoxyphenyl)-methyl]amino]- 1-(1H-indol-3-ylmethyl) ethyl][1,4'-bipiperidine]- 1'-acetamide ([3H]LY303870) binds to a single class of sites with an equilibrium KD of 0.22 nM and a Bmax of 723 fmol/mg of protein. Unlabeled LY303870 potently inhibited the binding with an IC50 of 0.56 nM, whereas the less active (S)-enantiomer (LY306155) was substantially less potent. The nonpeptide NK-1 antagonists (+/-)-CP96,345 and (+/-)-RP 67580 had IC50 values of 0.74 and 49 nM, respectively. Substance P (SP) was also a potent inhibitor with with an IC50 of 3.1 nM. The inhibition by SP could be separated into two components: a high-affinity component with a Ki of 0.53 nM and a lower-affinity component with a Ki of 155 nM. Addition of 100 microM guanylyl 5'-imidodiphosphate [Gpp(NH)p] in the incubation increased the relative amount of the low-affinity agonist state of the receptor. Consistent with the antagonist properties of LY303870, the dissociation rate of [3H]-LY303870 was not changed by the presence of 100 microM Gpp(NH)p. The distribution of [3H]LY303870 binding sites in the guinea pig brain closely matched the distribution of NK-1 receptors labeled by [3H]SP. Therefore, [3H]LY303870 is a potent and selective antagonist radioligand for NK-1 receptors in guinea pig brain. In addition, regulation of NK-1 agonist affinity by guanine nucleotides is similar to that seen for monoaminergic receptors.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Indoles,
http://linkedlifedata.com/resource/pubmed/chemical/LY 303870,
http://linkedlifedata.com/resource/pubmed/chemical/Piperidines,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Neurokinin-1,
http://linkedlifedata.com/resource/pubmed/chemical/Substance P,
http://linkedlifedata.com/resource/pubmed/chemical/Tritium
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pubmed:status |
MEDLINE
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pubmed:month |
Mar
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pubmed:issn |
0022-3042
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
66
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
1095-102
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pubmed:dateRevised |
2004-11-17
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pubmed:meshHeading |
pubmed-meshheading:8769871-Animals,
pubmed-meshheading:8769871-Autoradiography,
pubmed-meshheading:8769871-Binding Sites,
pubmed-meshheading:8769871-Brain,
pubmed-meshheading:8769871-Cell Line,
pubmed-meshheading:8769871-Corpus Striatum,
pubmed-meshheading:8769871-Guinea Pigs,
pubmed-meshheading:8769871-Humans,
pubmed-meshheading:8769871-Indoles,
pubmed-meshheading:8769871-Piperidines,
pubmed-meshheading:8769871-Receptors, Neurokinin-1,
pubmed-meshheading:8769871-Substance P,
pubmed-meshheading:8769871-Tissue Distribution,
pubmed-meshheading:8769871-Tritium
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pubmed:year |
1996
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pubmed:articleTitle |
[3H]LY303870, a novel nonpeptide radioligand for the NK-1 receptor.
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pubmed:affiliation |
CNS Research, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana 46285, USA.
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pubmed:publicationType |
Journal Article
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