Linked Life Data

12626359

Source:http://linkedlifedata.com/resource/pubmed/id/12626359

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2003-3-10
pubmed:abstractText
Oxidant stress contributes to the pathogenesis of hypoxic-ischemic encephalopathies. Platelet-activating factor (PAF) is generated during oxidant stress. We studied the vasomotor mode of actions of PAF on periventricular (PV) microvessels of fetal ( approximately 75% of term), newborn (1-3 days), and adult pigs. PAF constricted PV microvessels from fetal (29.27 +/- 2.6%) and newborn (22.14 +/- 3.2%) pigs but was ineffective in adults (<2.5%). Specific [(3)H]PAF binding was greater in fetus and newborn than in adults; a concordant developmental PAF-induced inositol phosphate formation was observed. PAF-induced vasoconstriction was abrogated by thromboxane A(2) (TXA(2)) synthase and receptor inhibitors, calcium channel blockers, and by removal of endothelium; vasoconstriction to TXA(2) mimetic U-46619 did not differ with age. Immunoreactive TXA(2) synthase expression and PAF-evoked TXA(2) formation revealed a fetus> newborn>adult profile. Thus the greater PAF-induced PV microvascular constriction in younger subjects seems attributable to greater PAF receptor density and mostly secondary to TXA(2) formation from endothelium. The resulting decrease in blood flow may contribute to the increased vulnerability of the PV brain regions to oxidant stress-induced injury in immature subjects.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0363-6119
pubmed:author
pubmed:issnType
Print
pubmed:volume
284
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
R928-35
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Increased platelet-activating factor-induced periventricular brain microvascular constriction associated with immaturity.
pubmed:affiliation
Centre de Recherche de l'Hôpital Sainte-Justine, Department of Pediatrics and Pharmacology, Université de Montréal, Montréal, H3T 1C5.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't