Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1996-12-3
pubmed:abstractText
The impact of in vivo ischaemia and ischaemia-reperfusion (I-R) on mitochondrial respiratory function was investigated in hypertrophied (HP) hearts with aortic constriction compared with control hearts using an open-chest rat surgical model. Moreover, mitochondrial susceptibility to superoxide radicals (O2-.) in vitro was examined in HP and control hearts with or without I-R. With the site I substrates pyruvate-malate, mitochondrial state 4 (basal) respiration and the respiratory control index (RCI) were not affected by either ischaemia alone or I-R in both HP and control hearts. State 3 (ADP-stimulated) respiration was increased with I-R in control hearts, but showed a reduction after I-R in the HP hearts. Exposure of mitochondria to O2-. (20 nM hypoxanthine in the presence of 0.13 unit mL-1 xanthine oxidase) significantly increased state 4 respiration, whereas state 3 respiration and RCI were decreased in all treatment groups. I-R hearts in both HP and control showed greater increases in state 4 respiration with O2-. than either sham or ischaemic hearts. HP hearts exhibited a significantly lesser extent of inhibition in state 3 respiration and RCI by O2-. compared with control hearts. These changes in mitochondrial respiratory properties were not observed with the site II substrate succinate. Myocardial reduced vs. oxidized glutathione ratio was significantly decreased after I-R in both control and HP hearts. Malondialdehyde content showed an increase with I-R, but the increase was significant only in control hearts. These data indicate that short-term in vivo I-R does not impair heart mitochondrial respiratory function, but renders the organelles more vulnerable to imposed oxidative stress. Mitochondria from the HP hearts are more resistant to free radical damage under normal and ischaemic conditions; however, this advantage is severely compromised after reperfusion.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0001-6772
pubmed:author
pubmed:issnType
Print
pubmed:volume
156
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
51-60
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Ischaemia-reperfusion induced alterations of mitochondrial function in hypertrophied rat heart.
pubmed:affiliation
Department of Kinesiology, University of Illinois, Urbana-Champaign, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't