Linked Life Data

8958128

Source:http://linkedlifedata.com/resource/pubmed/id/8958128

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1997-4-10
pubmed:abstractText
The effects of hydroxyl radical exposure of intact cardiomyocytes on sarcoplasmic reticulum (SR) function were investigated. For this purpose, isolated rat heart myocytes were exposed briefly (1 min) to the hydroxyl radical generating system (H2O2/FeCl2 or FeSO4) or 5-5'-dithiobis-nitrobenzoic acid (DTNB), a sulfhydryl oxidizing reagent, and following this a SR-enriched fraction was isolated. Marked decreases in the SR calcium uptake activities were seen in the myocytes exposed to either the hydroxyl radical-generating system or DTNB. The exposure of myocytes to the hydroxyl radical, but not DTNB, markedly increased the amount of malonyldialdehyde (MDA) in the subsequently isolated SR. Total sulfhydryl group content in SR was decreased by exposure of myocytes to DTNB. Further, there was a significant decrease in [3H]-NEM binding to SR isolated from the hydoxyl radical-treated myocytes indicating that sulfhydryl groups are affected (oxidized). Both mannitol and catalase were found to offer complete protection against the inhibitory effect of peroxide +/- iron on calcium uptake. Also the above-mentioned alterations in both MDA and sulfhydryl group content were prevented by mannitol and catalase. Exogenously added cyclic AMP-dependent protein kinase (A-PK) or calmodulin (CAM) increased SR calcium uptake activity. In the SR isolated from the treated myocytes, the stimulatory effects of A-PK and CAM were also seen, although under all assay conditions calcium uptakes were of lower magnitude. The findings are consistent with the view that the damaging effect of the hydroxyl radical and DTNB on the functioning of SR occurs rapidly in the intact cardiomyocytes. The hydroxyl radical-provoked damage involves both protein sulfhydryl and lipid oxidation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0891-5849
pubmed:author
pubmed:issnType
Print
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
37-47
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Sarcoplasmic reticulum Ca(2+)-pump dysfunction in rat cardiomyocytes briefly exposed to hydroxyl radicals.
pubmed:affiliation
Department of Physiology, College of Medicine, University of Saskatchewan, Saskatoon, Canada.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't