Linked Life Data

2258716

Source:http://linkedlifedata.com/resource/pubmed/id/2258716

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1991-1-31
pubmed:abstractText
We have studied in single cardiac ventricular cells of guinea pig the ionic translocation mechanism of the electrogenic Na-Ca exchange, i.e., whether Na and Ca ions countercross the membrane simultaneously or consecutively with "ping pong" kinetics. The dose-response relation between the external Ca concentrations [( Ca]o) and the current density of the outward Na-Ca exchange current were measured at three different intracellular Na concentrations [( Na]i) in the absence of external Na. Nonlinear regression curves of the dose-response relation obtained by computer revealed Michaelis-Menten type hyperbola from which the [Ca]o giving a half-maximal response (apparent KmCao or K'mCao) and the apparent maximum current magnitude (I'max) were estimated at each [Na]i. As [Na]i increased, the K'mCao increased progressively and the value of K'mCao/I'max tended to decrease. These results are consistent with the simultaneous mechanism. The K'mCao/I'max values, however, were small and close to each other, so it was not possible to completely preclude a consecutive mechanism.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-1295
pubmed:author
pubmed:issnType
Print
pubmed:volume
96
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
777-88
pubmed:dateRevised
2008-11-20
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Translocation mechanism of Na-Ca exchange in single cardiac cells of guinea pig.
pubmed:affiliation
National Institute for Physiological Sciences, Okazaki, Japan.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't