Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4 Pt 1
pubmed:dateCreated
1993-12-3
pubmed:abstractText
Chronic hypoxia induces a hyperadrenergic state which down-regulates beta-adrenergic receptors (beta-AR) in the heart. We visualized lung beta-AR binding sites after adaptation to chronic hypoxia by autoradiography of whole lung sections labeled with 50 pM 125I-labeled pindolol. A low concentration of agonist (32 nM isoproterenol) selectively masked beta-ARs with high affinity for agonists. Total specific beta-AR binding increased twofold with hypoxia. In both the control and hypoxic lung sections, 60-70% of the beta-ARs were in a high-affinity state, which could be reversed by guanine nucleotide. Autoradiography revealed a high density of high- and low-affinity beta-AR sites in lung parenchyma, predominantly involving alveolar walls, but also the walls of airways and blood vessels. The distribution of high- and low-affinity beta-AR within the lung was qualitatively identical. Hypoxia increased beta-AR binding without affecting its distribution. The majority of the additional beta-ARs induced during adaptation to chronic hypoxia are in the high-affinity state, and are thus of probable functional significance.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
265
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
L389-94
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Visualization of high- and low-affinity beta-adrenergic receptors in rat lung: upregulation by chronic hypoxia.
pubmed:affiliation
Department of Pediatrics, Rainbow Babies and Children's Hospital, Cleveland, Ohio.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.