Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2006-8-10
pubmed:abstractText
Bronchus-derived relaxing factor (BrDRF) decreases contractility of newborn rat pulmonary arteries (PA) and is dependent on nitric oxide (NO) synthesis. In vivo, this factor appears to gain access via the adventitial side of the PA. However, the adventitia has been reported to be a barrier to NO. We studied the effect of an adjacent bronchus on PA contractility to norepinephrine in nine juvenile lambs in the presence and absence of inhibitors of the NO pathway (LNA, ODQ, and Rp-8-Br-PET-cGMPS), cytochrome P-450 inhibitor (17-ODYA), perivascular nerve activity blocker (TTX), and superoxide scavenger (tiron), and following disruption of bronchial epithelium. We also evaluated whether BrDRF was effective on both the endothelial and/or adventitial side of PA. Fifth-generation PA rings with and without an attached bronchus were contracted in standard baths with norepinephrine. PA were dissected, cut open, and placed in a sided chamber in which adventitial and endothelial sides of the PA were exposed to unattached bronchus separately. Norepinephrine (10(-8) to 10(-5) M) contractions were expressed as a fraction of maximal KCl (118 mM) contractions. Norepinephrine contractions were significantly reduced by the presence of an attached bronchus, an effect reversed by pretreatment with LNA, ODQ, and Rp-8-Br-PET-cGMPS, and removal of bronchial epithelium. Unattached bronchus in the bath perfusing the adventitial side was effective in inhibiting the contractile response in PA. NO gas relaxed PA when administered on the endothelial side only. We speculate that BrDRF is a diffusible factor that crosses the adventitia and stimulates production of NO within the PA.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1040-0605
pubmed:author
pubmed:issnType
Print
pubmed:volume
291
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
L473-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Adjacent bronchus attenuates pulmonary arterial contractility.
pubmed:affiliation
Department of Pediatrics, State University of New York at Buffalo, Center for Developmental Biology of the Lung, USA. slakshmi@buffalo.edu
pubmed:publicationType
Journal Article, Comparative Study, In Vitro