Linked Life Data

16137732

Source:http://linkedlifedata.com/resource/pubmed/id/16137732

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2005-12-19
pubmed:abstractText
The sequelae of mercury intoxication include induction of apoptosis. In nucleated cells, Hg2+-induced apoptosis involves mitochondrial damage. The present study has been performed to elucidate effects of Hg2+ in erythrocytes which lack mitochondria but are able to undergo apoptosis-like alterations of the cell membrane. Previous studies have documented that activation of a Ca2+-sensitive erythrocyte scramblase leads to exposure of phosphatidylserine at the erythrocyte surface, a typical feature of apoptotic cells. The erythrocyte scramblase is activated by osmotic shock, oxidative stress and/or energy depletion which increase cytosolic Ca2+ activity and/or activate a sphingomyelinase leading to formation of ceramide. Ceramide sensitizes the scramblase to Ca2+. The present experiments explored the effect of Hg2+ ions on erythrocytes. Phosphatidylserine exposure after mercury treatment was estimated from annexin binding as determined in FACS analysis. Exposure to Hg2+ (1 microM) indeed significantly increased annexin binding from 2.3+/-0.5% (control condition) to 23+/-6% (n=6). This effect was paralleled by activation of a clotrimazole-sensitive K+-selective conductance as measured by patch-clamp recordings and by transient cell shrinkage. Further experiments revealed also an increase of ceramide formation by approximately 66% (n=7) after challenge with mercury (1 microM). In conclusion, mercury ions activate a clotrimazole-sensitive K+-selective conductance leading to transient cell shrinkage. Moreover, Hg2+ increases ceramide formation. The observed mechanisms could similarly participate in the triggering of apoptosis in nucleated cells by Hg2+.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0041-008X
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
210
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
116-22
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Stimulation of erythrocyte phosphatidylserine exposure by mercury ions.
pubmed:affiliation
Department of Physiology, University of Tübingen, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't