Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1989-9-8
pubmed:abstractText
Indirect evidence exists that the reperfusion of ischemic tissue activates white blood cells. Thus local and systemic reperfusion injuries are prevented by making animals leukopenic or by inhibiting white blood cell lung entrapment by blocking thromboxane A2 generation. This study tests directly whether ischemia and reperfusion activates neutrophils, as measured by their oxidative burst, and whether thromboxane mediates this event. Anesthetized rats underwent 4 hours of bilateral hind limb tourniquet ischemia followed by 60 minutes of reperfusion. Plasma thromboxane B2 levels increased to 2750 pg/ml at 5 minutes of reperfusion, higher than the sham control (n = 36) value of 370 pg/ml (p less than 0.01). In untreated ischemic animals (n = 30) the intracellular H2O2 production of circulating neutrophils, as assayed flow cytometrically by dichlorofluorescein oxidation, increased from a preischemic value of 133 to a peak of 251 femtomoles dichlorofluorescein/neutrophil at 5 minutes of reperfusion (p less than 0.01). Treatment of neutrophils with phorbol myristate acetate (PMA) 10(-7) mol/L led to a 91% increase in neutrophil H2O2 production before ischemia, and 5 minutes after reperfusion there was an enhanced response to PMA of 222% (p less than 0.01). Pretreatment of animals with the thromboxane-synthetase inhibitor OKY 046 (n = 36) prevented ischemia-induced thromboxane generation, neutrophil H2O2 production (p less than 0.05), as well as the enhanced response to PMA stimulation (p less than 0.05). Treatment with the thromboxane-receptor antagonist SQ 29,548 (n = 36) did not affect the increase in plasma thromboxane levels after ischemia but was as effective as OKY 046 in preventing the ischemia-induced increase in neutrophil H2O2 production and the enhanced response to PMA stimulation. These data indicate that lower-torso ischemia leads to neutrophil activation, manifest by H2O2 production, an event mediated by thromboxane.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0039-6060
pubmed:author
pubmed:issnType
Print
pubmed:volume
106
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
224-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Thromboxane mediates the ischemia-induced neutrophil oxidative burst.
pubmed:affiliation
Department of Surgery, Brigham and Women's Hospital, Boston, MA 02115.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't