Linked Life Data

20550942

Source:http://linkedlifedata.com/resource/pubmed/id/20550942

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2010-7-19
pubmed:abstractText
Fluctuating extracellular Ca2+ regulates many aspects of neuronal (patho)physiology including cell metabolism and respiration. Using fluorescence-based intracellular oxygen sensing technique, we demonstrate that depletion of extracellular Ca2+ from 1.8 to < or = 0.6 mM by chelation with EGTA induces a marked spike in O2 consumption in differentiated PC12 cells. This respiratory response is associated with the reduction in cytosolic and mitochondrial Ca2+, minor depolarization on the mitochondrial membrane, moderate depolarization of plasma membrane, and no changes in NAD(P)H and ATP. The response is linked to the influx of extracellular Na+ and the subsequent activation of mitochondrial Na+/Ca2+ and Na+/H+ exchange. The mitochondrial Na+/Ca2+ exchanger ((m)NCX) activated by Na+ influx reduces Ca2+ and increases Na+ levels in the mitochondrial matrix. The excess of Na+ activates the mitochondrial Na+/H+ exchanger (NHE) increasing the outward pumping of protons, electron transport and O2 consumption. Reduction in extracellular Na+ and inhibition of Na+ influx through the receptor operated calcium channels and plasmalemmal NHE reduce the respiratory response. Inhibition of the (m)NCX, L-type voltage gated Ca2+ channels or the release of Ca2+ from the endoplasmic reticulum also reduces the respiratory spike, indicating that unimpaired intercompartmental Ca2+ exchange is critical for response development.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-3002
pubmed:author
pubmed:copyrightInfo
2010 Elsevier B.V. All rights reserved.
pubmed:issnType
Print
pubmed:volume
1797
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1627-37
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Extracellular calcium depletion transiently elevates oxygen consumption in neurosecretory PC12 cells through activation of mitochondrial Na+/Ca2+ exchange.
pubmed:affiliation
Biochemistry Department, University College Cork, College Road, Cork, Ireland. a.zhdanov@ucc.ie
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't