Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
26
pubmed:dateCreated
1986-4-3
pubmed:abstractText
The reversal of the rat liver microsomal Ca2+-ATPase transport cycle was studied. Microsomes were loaded with 45Ca2+ (approximately 30 nmol/mg of protein) in an ATP-dependent process, and the time dependency of the microsomal 45Ca2+ efflux was determined with various ADP and inorganic phosphate (Pi) concentrations. Pseudo-first-order rate constants (K'e) for 45Ca2+ efflux were determined. Although there was considerable 45Ca2+ efflux in the absence of added ADP or Pi, the addition of ADP or Pi alone had minimal effects upon the K'e; in contrast, a 2.5-fold increase in the K'e was observed in the presence of both ADP and Pi. The apparent Km values for ADP and Pi were 4 microM and 0.22 mM, respectively. Stimulation of 45Ca2+ efflux by ADP and Pi was associated with ATP synthesis. The calcium ionophore A23187 prevented ATP synthesis, which indicates that the Ca2+ gradient facilitates the coupling of ATP synthesis to Ca2+ efflux.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
24
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7741-5
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Coupling of ATP synthesis to reversal of rat liver microsomal Ca2+-ATPase.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.