Linked Life Data

7678857

Source:http://linkedlifedata.com/resource/pubmed/id/7678857

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1993-3-4
pubmed:abstractText
A full-length clone coding for the rat alpha 7 nicotinic receptor subunit was isolated from an adult brain cDNA library and expressed in Xenopus oocytes. A significant proportion of the current through alpha 7-channels is carried by Ca2+. This Ca2+ influx then activates a Ca(2+)-dependent Cl- conductance, which is blocked by the chloride channel blockers niflumic and fluflenamic acid. Increasing the external NaCl concentration caused the reversal potentials for the alpha 7-channels and the Ca(2+)-dependent Cl- channels to be shifted in opposite directions. Under these conditions, agonist application activates a biphasic current with an initial inward current through alpha 7-channels followed by a niflumic acid- and fluflenamic acid-blockable outward current through Ca(2+)-dependent Cl- channels. A relative measure of the Ca2+ permeability was made by measuring the shift in the reversal potential caused by adding 10 mM Ca2+ to the external solution. Measurements made in the absence of Cl-, to avoid artifactual current through Ca(2+)-activated Cl- channels, indicate that alpha 7-homooligomeric channels have a greater relative Ca2+ permeability than the other nicotinic ACh receptors. Furthermore, alpha 7-channels have an even greater relative Ca2+ permeability than the NMDA subtype of glutamate receptors. High levels of alpha 7-transcripts were localized by in situ hybridization in the olfactory areas, the hippocampus, the hypothalamus, the amygdala, and the cerebral cortex. These results imply that alpha 7-containing receptors may play a role in activating calcium-dependent mechanisms in specific neuronal populations of the adult rat limbic system.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0270-6474
pubmed:author
pubmed:issnType
Print
pubmed:volume
13
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
596-604
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:7678857-Amino Acid Sequence, pubmed-meshheading:7678857-Animals, pubmed-meshheading:7678857-Base Sequence, pubmed-meshheading:7678857-Brain Chemistry, pubmed-meshheading:7678857-Bungarotoxins, pubmed-meshheading:7678857-Calcium, pubmed-meshheading:7678857-Cations, pubmed-meshheading:7678857-Chloride Channels, pubmed-meshheading:7678857-Cloning, Molecular, pubmed-meshheading:7678857-Electric Conductivity, pubmed-meshheading:7678857-Female, pubmed-meshheading:7678857-Flufenamic Acid, pubmed-meshheading:7678857-Ion Channels, pubmed-meshheading:7678857-Membrane Proteins, pubmed-meshheading:7678857-Molecular Sequence Data, pubmed-meshheading:7678857-Niflumic Acid, pubmed-meshheading:7678857-Oocytes, pubmed-meshheading:7678857-Permeability, pubmed-meshheading:7678857-RNA, Messenger, pubmed-meshheading:7678857-Rats, pubmed-meshheading:7678857-Receptors, Nicotinic, pubmed-meshheading:7678857-Sodium Chloride, pubmed-meshheading:7678857-Tissue Distribution, pubmed-meshheading:7678857-Transfection, pubmed-meshheading:7678857-Xenopus laevis
pubmed:year
1993
pubmed:articleTitle
Molecular cloning, functional properties, and distribution of rat brain alpha 7: a nicotinic cation channel highly permeable to calcium.
pubmed:affiliation
Division of Neuroscience, Baylor College of Medicine, Houston, Texas 77030.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.