Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2000-10-12
pubmed:abstractText
The pro-inflammatory characteristics of tumor necrosis factor-alpha (TNF-alpha) have been extensively characterized in in vitro systems. Furthermore, this cytokine has been shown to play a pivotal role in airways inflammation in asthma. Since the airway vasculature also performs an essential function in inflammatory cell transit to the airways, experiments were performed to determine the effects of TNF-alpha on bronchial vascular resistance (BVR). In anesthetized, ventilated sheep, the bronchial artery (BA) was cannulated and perfused with autologous blood. BVR was defined as inflow pressure/flow and averaged 6.3 +/- 0.2 mmHg. ml(-1). min(-1) (+/-SE) for the 25 sheep studied. Recombinant human TNF-alpha (10 microg for 20 or 40 min) infused directly into the BA resulted in a significant decrease in BVR to 87% of baseline (P < 0.05). This vasodilation was followed by a reversal of tone by 120 min and a sustained increase in BVR to 126% of baseline (P < 0.05). Since others have shown TNF-alpha caused coronary vasoconstriction through endothelial release of endothelin-1 (ET-1), an ET-1 antagonist was used to block bronchial vasoconstriction. BQ-123, a selective ET(A) receptor antagonist, was delivered to the bronchial vasculature prior to TNF-alpha challenge. Attenuation of bronchial vasoconstriction was observed at 120 min (P < 0.03). Thus TNF-alpha causes bronchial vasoconstriction by the secondary release of ET-1. Although TNF-alpha exerts pro-inflammatory actions on most cells of the airways, vasoactive properties of this cytokine likely further contribute to the inflammatory status of the airways.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0363-6135
pubmed:author
pubmed:issnType
Print
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H946-51
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
TNF-alpha induced bronchial vasoconstriction.
pubmed:affiliation
Department of Medicine, Johns Hopkins University, Baltimore, Maryland 21224, USA. wagnerem@jhmi.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.