Linked Life Data

3217238

Source:http://linkedlifedata.com/resource/pubmed/id/3217238

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1989-3-8
pubmed:abstractText
Isolated skin of the clawed frog Xenopus laevis was mounted in an Ussing-chamber. The transcellular sodium-current (INa) was identified either as amiloride-blockable (10(-3) mol/l) short-circuit current (ISC), or by correcting ISC for the shunt-current obtained with mucosal Tris. A dose of 10 mmol/l Cd2+ applied to the mucosal side increased the current by about 70%. The half-maximal effect was reached at a Cd2+-concentration of 2.6 mmol/l (in NaCl-Ringer). The quick and fully reversible effect of Cd2+ could not be seen when 10(-3) mol/l amiloride was placed in the outer, Na+-containing solution, nor when Na+ was replaced by Tris. This suggests that Cd2+ stimulates INa. Cd2+ interfered with the Na+-current self-inhibition, and therefore with the saturation of INa by increasing the apparent Michaelis constant (KNa) of this process. The "INa recline" after stepping up mucosal [Na+] was much reduced in presence of Cd2+. Ca2+-ions on the mucosal side had an identical effect to Cd2+, and 10 mmol/l Ca2+ increase INa by about 100%. The half-maximal effect was obtained with 4.4 mmol/l Ca2+. The mechanism of INa-stimulation by Ca2+ did not seem to differ from that of Cd2+. Thus, although of low Na+-transport capacity, Xenopus skin appears to be as good a model for Na+-transporting epithelia as Ranidae skin, with the exception of the calcium effect which, so far, has not been reported for Ranidae.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0031-6768
pubmed:author
pubmed:issnType
Print
pubmed:volume
413
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
174-80
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
A novel synergistic stimulation of Na+-transport across frog skin (Xenopus laevis) by external Cd2+- and Ca2+-ions.
pubmed:affiliation
Institut für Tierphysiologie und angewandte Zoologie, Freie Universität Berlin, Federal Republic of Germany.
pubmed:publicationType
Journal Article, In Vitro