Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1998-12-23
pubmed:abstractText
It has been proposed that P glycoprotein (Pgp) expression is associated with swelling-activated Cl- currents in multidrug-resistant cells. The Pgp substrate vinblastine and the modulator verapamil produced a reversible concentration-dependent block of swelling-activated Cl- currents in both a drug-sensitive cell line (MCF-7) and a Pgp-expressing derivative (BC19/3). The similarity of the results obtained in both cell lines suggests that the mechanism of block is not related to Pgp expression and supports the hypothesis that Pgp expression is not necessary for the swelling activation of Cl- currents. In contrast to the results obtained with vinblastine, two other cytoskeleton-disrupting agents, colchicine and cytochalasin D, were not able to affect the swelling-activated Cl- currents in either cell line. The data provided no evidence for the involvement of the cytoskeleton in the swelling activation of Cl- channels in these cell lines. The Cl- channel blockers, 5-nitro-2-(3-phenylpropylamino)benzoic acid and 4, 4'-diisothiocyanatostilbene-2,2'-disulfonic acid, each produced a similar reversible concentration-dependent block in the swelling-activated currents in both the Pgp-expressing and nonexpressing cells. This strongly suggests that the Cl- channel(s) responsible for the swelling-dependent current in both cell lines are the same and, since MCF-7 cells do not express Pgp, that Pgp is not the channel responsible for the volume-activated Cl- currents in these cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/4,4'-Diisothiocyanostilbene-2,2'-Dis..., http://linkedlifedata.com/resource/pubmed/chemical/5-(4-nitrophenyl)-2,4-pentadienal, http://linkedlifedata.com/resource/pubmed/chemical/Chloride Channels, http://linkedlifedata.com/resource/pubmed/chemical/Colchicine, http://linkedlifedata.com/resource/pubmed/chemical/Cytochalasin D, http://linkedlifedata.com/resource/pubmed/chemical/Etoposide, http://linkedlifedata.com/resource/pubmed/chemical/Hypertonic Solutions, http://linkedlifedata.com/resource/pubmed/chemical/Hypotonic Solutions, http://linkedlifedata.com/resource/pubmed/chemical/Meglumine, http://linkedlifedata.com/resource/pubmed/chemical/Nitrobenzenes, http://linkedlifedata.com/resource/pubmed/chemical/P-Glycoprotein, http://linkedlifedata.com/resource/pubmed/chemical/Verapamil, http://linkedlifedata.com/resource/pubmed/chemical/Vinblastine
pubmed:status
MEDLINE
pubmed:issn
1015-8987
pubmed:author
pubmed:issnType
Print
pubmed:volume
8
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
246-60
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Swelling-activated chloride currents in a drug-sensitive cell line and a P glycoprotein-expressing derivative are underlied by channels with the same pharmacological properties.
pubmed:affiliation
Sealy Center for Molecular Science, The University of Texas Medical Branch, Galveston, Tex., USA. horton1@niehs.nih.gov
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't