Linked Life Data

9436175

Source:http://linkedlifedata.com/resource/pubmed/id/9436175

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1998-3-4
pubmed:abstractText
Alveolar macrophages (m phi) possess two parallel mechanisms for plasmalemmal H+ extrusion: a V-type H+ pump (V-ATPase) and a Na+/H+ exchanger (NHE). To investigate the coordinated functioning of the H+ extruders for m phi intracellular pH (pHi) regulation, we investigated the effects of the plant lectin concanavalin A (ConA) on resident alveolar m phi from rabbits. ConA (1 microM, 30-min pretreatment) activated the m phi for phagocytosis of opsonized Escherichia coli. ConA activation did not affect the baseline pHi of m phi or the initial rate of pHi recovery (dpHi/dt) from an intracellular acid load (acid-loaded pHi nadir approximately 6.9). However, the contributions of Na(+)-independent H+ transport (i.e. V-ATPase activity) and Na(+)-dependent H+ transport (i.e. NHE activity) to dpHi/dt were altered significantly. The lectin stimulated Na+/H+ exchange and inhibited V-ATPase activity. In control m phi, V-ATPase-mediated H+ extrusion was responsible for > 80% of dpHi/dt. Conversely, in ConA-treated m phi, Na+/H+ exchange was responsible for approximately 65% of dpHi/dt, and V-ATPase activity was responsible for only 35% of dpHi/dt. These results underscore the complex mechanisms and signaling pathways that coordinate the activities of cellular acid-base transporters in m phi pHi regulation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0341-2040
pubmed:author
pubmed:issnType
Print
pubmed:volume
176
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
25-34
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Effects of concanavalin A on Na(+)-dependent and Na(+)-independent mechanisms for H+ extrusion in alveolar macrophages.
pubmed:affiliation
Department of Internal Medicine, University of Texas Medical Branch, Galveston 77555-0876, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't