Linked Life Data

15143149

Source:http://linkedlifedata.com/resource/pubmed/id/15143149

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
Pt 12
pubmed:dateCreated
2004-5-14
pubmed:abstractText
Transport of the prototypical organic cation tetraethylammonium (TEA) by the Malpighian tubules, ureters and gut of Drosophila melanogaster was studied using two novel electrophysiological techniques. Both techniques exploited the high selectivity of the cation exchanger potassium tetra-p-chlorophenylborate for tetraalkylammonium compounds relative to inorganic cations such as K(+). In the first technique, TEA fluxes were measured using a non-invasive self-referencing TEA-selective microelectrode positioned in the unstirred layer near the surface of each tissue. TEA fluxes from bath to lumen as large as 6 pmol cm(-2) s(-1) were measured across the lower (reabsorptive) segment of the Malpighian tubule and the ureter bathed in saline containing 0.1 mmol l(-1) TEA. Corresponding bath-to-lumen fluxes across the secretory main segment of the Malpighian tubule and the posterior midgut were approximately 1 pmol cm(-2) s(-1). TEA transport by the lower Malpighian tubule was enhanced by hyperpolarization of the basolateral membrane potential and was inhibited by cimetidine, quinidine, vinblastine and verapamil. In the second technique, TEA concentration was measured using a TEA-selective microelectrode positioned in droplets of fluid secreted by Malpighian tubules set up in saline droplets under oil in a Ramsay assay. Results from the Ramsay assay confirmed the dominant role of the lower Malpighian tubule in net transepithelial secretion of TEA and inhibition of TEA transport by cimetidine. Kinetic parameters (J(max) and K(t)) were determined using both approaches.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-0949
pubmed:author
pubmed:issnType
Print
pubmed:volume
207
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2173-84
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Organic cation transport by Malpighian tubules of Drosophila melanogaster: application of two novel electrophysiological methods.
pubmed:affiliation
Department of Biology, McMaster University, 1280 Main Street West, Hamilton, Canada L8S 4K1. rheaulmr@mcmaster.ca
pubmed:publicationType
Journal Article, Comparative Study