Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2009-6-8
pubmed:abstractText
Here we report effect of ischemia-reperfusion on mitochondrial Ca2+ uptake and activity of complexes I and IV in rat hippocampus. By performing 4-vessel occlusion model of global brain ischemia, we observed that 15 min ischemia led to significant decrease of mitochondrial capacity to accumulate Ca2+ to 80.8% of control whereas rate of Ca2+ uptake was not significantly changed. Reperfusion did not significantly change mitochondrial Ca2+ transport. Ischemia induced progressive inhibition of complex I, affecting final electron transfer to decylubiquinone. Minimal activity of complex I was observed 24 h after ischemia (63% of control). Inhibition of complex IV activity to 80.6% of control was observed 1 h after ischemia. To explain the discrepancy between impact of ischemia on rate of Ca2+ uptake and activities of both complexes, we performed titration experiments to study relationship between inhibition of particular complex and generation of mitochondrial transmembrane potential (DeltaPsi(m)). Generation of a threshold curves showed that complex I and IV activities must be decreased by approximately 40, and 60%, respectively, before significant decline in DeltaPsi(m) was documented. Thus, mitochondrial Ca2+ uptake was not significantly affected by ischemia-reperfusion, apparently due to excess capacity of the complexes I and IV. Inhibition of complex I is favourable of reactive oxygen species (ROS) generation. Maximal oxidative modification of membrane proteins was documented 1 h after ischemia. Although enhanced formation of ROS might contribute to neuronal injury, depressed activities of complex I and IV together with unaltered rate of Ca2+ uptake are conditions favourable of initiation of other cell degenerative pathways like opening of mitochondrial permeability transition pore or apoptosis initiation, and might represent important mechanism of ischemic damage to neurones.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/2,3-dimethoxy-5-methyl-6-decyl-1,4-b..., http://linkedlifedata.com/resource/pubmed/chemical/Adaptor Protein Complex 1, http://linkedlifedata.com/resource/pubmed/chemical/Adaptor Protein Complex 4, http://linkedlifedata.com/resource/pubmed/chemical/Azides, http://linkedlifedata.com/resource/pubmed/chemical/Calcium, http://linkedlifedata.com/resource/pubmed/chemical/Ferricyanides, http://linkedlifedata.com/resource/pubmed/chemical/Membrane Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Reactive Oxygen Species, http://linkedlifedata.com/resource/pubmed/chemical/Rotenone, http://linkedlifedata.com/resource/pubmed/chemical/Ubiquinone, http://linkedlifedata.com/resource/pubmed/chemical/Uncoupling Agents, http://linkedlifedata.com/resource/pubmed/chemical/hexacyanoferrate III
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
1573-6903
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
34
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1469-78
pubmed:meshHeading
pubmed-meshheading:19252983-Adaptor Protein Complex 1, pubmed-meshheading:19252983-Adaptor Protein Complex 4, pubmed-meshheading:19252983-Animals, pubmed-meshheading:19252983-Azides, pubmed-meshheading:19252983-Brain Ischemia, pubmed-meshheading:19252983-Calcium, pubmed-meshheading:19252983-Ferricyanides, pubmed-meshheading:19252983-Hippocampus, pubmed-meshheading:19252983-Male, pubmed-meshheading:19252983-Membrane Potentials, pubmed-meshheading:19252983-Membrane Proteins, pubmed-meshheading:19252983-Mitochondria, pubmed-meshheading:19252983-Mitochondrial Diseases, pubmed-meshheading:19252983-Rats, pubmed-meshheading:19252983-Rats, Wistar, pubmed-meshheading:19252983-Reactive Oxygen Species, pubmed-meshheading:19252983-Reperfusion Injury, pubmed-meshheading:19252983-Rotenone, pubmed-meshheading:19252983-Spectrometry, Fluorescence, pubmed-meshheading:19252983-Ubiquinone, pubmed-meshheading:19252983-Uncoupling Agents
pubmed:year
2009
pubmed:articleTitle
Mitochondrial calcium transport and mitochondrial dysfunction after global brain ischemia in rat hippocampus.
pubmed:affiliation
Institute of Biochemistry, Jessenius Faculty of Medicine, Comenius University, Mala Hora 4, 03601 Martin, Slovak Republic. racay@jfmed.uniba.sk
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't