Linked Life Data

9351889

Source:http://linkedlifedata.com/resource/pubmed/id/9351889

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1998-2-19
pubmed:abstractText
Previous work from this laboratory has shown that apical membrane sodium channel activity is stimulated by serosal hyposmotic solutions (Wills, Millinoff & Crowe, 1991). In the present study, we determined whether this stimulation of sodium transport is additive with the actions of prostaglandin E2 (PGE2) or cyclic AMP (cAMP). Addition of exogenous PGE2 (100 nM; serosal bath) to isosmotic solutions led to large increases in the amiloride-sensitive short-circuit current (Isc) and transepithelial conductance (Gt), whereas no significant effects of PGE2 were observed in hyposmotic serosal solutions. Subsequent addition of mucosal amiloride reduced Isc by approximately 95% and Gt by approximately 60%. Inhibition of endogenous PGE2 production by blockers of phospholipase A2 activity (quinacrine or 3[4-octadecyl]-benzoylacrylic acid; OBBA), or inhibition of cyclooxygenase activity by indomethacin reduced the stimulation of Isc and Gt by hyposmotic solutions. Addition of forskolin (FSK) or 3-Isobutyl-1-methylxanthine (IBMX) also resulted in approximately twofold increases in the amiloride-sensitive Isc and Gt and abolished the effects of subsequent hyposmotic challenge. The effects of forskolin, PGE2, and hyposmotic challenge were diminished by pretreatment with H89, a protein kinase A (PKA) inhibitor. We conclude that osmotic regulation of sodium channel activity interacts with multiple intracellular signaling pathways, specifically the arachidonic acid metabolic pathway and the cAMP/PKA intracellular messenger cascade.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-2631
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
160
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
27-38
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Osmotic regulation of Na+ transport across A6 epithelium: interactions with prostaglandin E2 and cyclic AMP.
pubmed:affiliation
Department of Physiology & Biophysics, University of Texas Medical Branch, Galveston 77555, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't