Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
26
|
| pubmed:dateCreated |
1995-8-10
|
| pubmed:abstractText |
A novel selective calcium channel antagonist peptide, SNX-325, has been isolated from the venom of the spider Segestria florentina. The peptide was isolated using as bioassays the displacement of radioiodinated omega-conopeptide SNX-230 (MVIIC) from rat brain synaptosomal membranes, as well as the inhibition of the barium current through cloned expressed calcium channels in oocytes. The primary sequence of SNX-325 is GSCIESGKSCTHSRSMKNGLCCPKSRCNCRQIQHRHDYLGKRKYSCRCS, which is a novel amino acid sequence. Solid-phase synthesis resulted in a peptide that is chromatographically identical with the native peptide and which has the same configuration of cysteine residues as the spider venom peptide omega-Aga-IVa [Mintz, I. M., et al., (1992) Nature 355, 827-829]. At micromolar concentrations, SNX-325 is an inhibitor of most calcium, but not sodium or potassium, currents. At nanomolar concentrations, SNX-325 is a selective blocker of the cloned expressed class B (N-type), but not class C (cardiac L), A, or E, calcium channels. SNX-325 is approximately equipotent with the N-channel selective omega-conopeptides (GVIA and MVIIA as well as closely related synthetic derivatives) in blocking the potassium induced release of tritiated norepinephrine from hippocampal slices (IC50s, 0.1-0.5 nM) and in blocking the barium current through cloned expressed N-channels in oocytes (IC50s 3-30 nM). By contrast, SNX-325 is 4-5 orders of magnitude less potent than is SNX-111 (synthetic MVIIA) at displacing radioiodinated SNX-111 from rat brain synaptosomal membranes. SNX-325 will be a useful comparative tool in further defining the function and pharmacology of the N- and possibly other types of high-voltage activated calcium channels.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channel Blockers,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channels,
http://linkedlifedata.com/resource/pubmed/chemical/Carboxypeptidases,
http://linkedlifedata.com/resource/pubmed/chemical/Cathepsin A,
http://linkedlifedata.com/resource/pubmed/chemical/Chymotrypsin,
http://linkedlifedata.com/resource/pubmed/chemical/Iodine Radioisotopes,
http://linkedlifedata.com/resource/pubmed/chemical/Ion Channels,
http://linkedlifedata.com/resource/pubmed/chemical/Peptide Fragments,
http://linkedlifedata.com/resource/pubmed/chemical/Peptides,
http://linkedlifedata.com/resource/pubmed/chemical/Spider Venoms,
http://linkedlifedata.com/resource/pubmed/chemical/omega-Conotoxins,
http://linkedlifedata.com/resource/pubmed/chemical/omega-conotoxin-MVIIC
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Jul
|
| pubmed:issn |
0006-2960
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:day |
4
|
| pubmed:volume |
34
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
N
|
| pubmed:pagination |
8341-7
|
| pubmed:dateRevised |
2009-11-19
|
| pubmed:meshHeading |
pubmed-meshheading:7541240-Amino Acid Sequence,
pubmed-meshheading:7541240-Animals,
pubmed-meshheading:7541240-Binding, Competitive,
pubmed-meshheading:7541240-Brain,
pubmed-meshheading:7541240-Calcium Channel Blockers,
pubmed-meshheading:7541240-Calcium Channels,
pubmed-meshheading:7541240-Carboxypeptidases,
pubmed-meshheading:7541240-Cathepsin A,
pubmed-meshheading:7541240-Chymotrypsin,
pubmed-meshheading:7541240-Female,
pubmed-meshheading:7541240-Iodine Radioisotopes,
pubmed-meshheading:7541240-Ion Channels,
pubmed-meshheading:7541240-Molecular Sequence Data,
pubmed-meshheading:7541240-Oocytes,
pubmed-meshheading:7541240-Organ Specificity,
pubmed-meshheading:7541240-Peptide Fragments,
pubmed-meshheading:7541240-Peptides,
pubmed-meshheading:7541240-Rats,
pubmed-meshheading:7541240-Sequence Homology, Amino Acid,
pubmed-meshheading:7541240-Spider Venoms,
pubmed-meshheading:7541240-Spiders,
pubmed-meshheading:7541240-Synaptosomes,
pubmed-meshheading:7541240-Xenopus,
pubmed-meshheading:7541240-omega-Conotoxins
|
| pubmed:year |
1995
|
| pubmed:articleTitle |
SNX-325, a novel calcium antagonist from the spider Segestria florentina.
|
| pubmed:affiliation |
Neurex Corporation, Menlo Park, California 94025-1012, USA.
|
| pubmed:publicationType |
Journal Article,
Comparative Study,
Research Support, Non-U.S. Gov't
|