Linked Life Data

10660526

Source:http://linkedlifedata.com/resource/pubmed/id/10660526

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2000-3-16
pubmed:abstractText
Upon activation of specific cell signaling, hepatocytes rapidly accumulate or release an amount of Mg(2+) equivalent to 10% of their total Mg(2+) content. Although it is widely accepted that Mg(2+) efflux is Na(+)-dependent, little is known about transporter identity and the overall regulation. Even less is known about the mechanism of cellular Mg(2+) uptake. Using sealed and right-sided rat liver plasma membrane vesicles representing either the basolateral (bLPM) or apical (aLPM) domain, it was possible to dissect three different Mg(2+) transport mechanisms based upon specific inhibition, localization within the plasma membrane, and directionality. The bLPM possesses only one Mg(2+) transporter, which is strictly Na(+)-dependent, bi-directional, and not inhibited by amiloride. The aLPM possesses two separate Mg(2+) transporters. One, similar to that in the bLPM because it strictly depends on Na(+) transport, and it can be differentiated from that of the bLPM because it is unidirectional and fully inhibited by amiloride. The second is a novel Ca(2+)/Mg(2+) exchanger that is unidirectional and inhibited by amiloride and imipramine. Hence, the bLPM transporter may be responsible for the exchange of Mg(2+) between hepatocytes and plasma, and vice versa, shown in livers upon specific metabolic stimulation, whereas the aLPM transporters can only extrude Mg(2+) into the biliary tract. The dissection of these three distinct pathways and, therefore, the opportunity to study each individually will greatly facilitate further characterization of these transporters and a better understanding of Mg(2+) homeostasis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
11
pubmed:volume
275
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3772-80
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Differential localization and operation of distinct Mg(2+) transporters in apical and basolateral sides of rat liver plasma membrane.
pubmed:affiliation
Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106-4970, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.