Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2001-5-17
pubmed:abstractText
Both isoproterenol and tidal fluctuations of muscle length inhibit active force development in activated airway smooth muscle. In this study, we show that length fluctuations in the range of amplitudes expected during quiet tidal breathing produce force inhibition that is equipotent with high concentrations of isoproterenol. Active force fell to 50% of its isometric value when the amplitude of the tidal stretch was 4% of muscle length. The relaxing effects of length fluctuations were insensitive to the specific contractile agonist, suggesting that the mechanism of action is largely independent of the particular signal transduction pathway and lies instead at the level of bridge dynamics. This idea is reinforced by the results of combining the relaxation effects of tidal fluctuations with those produced by isoproterenol at all but the highest concentrations studied (10(-5) M). Such a combination produces multiplicative effects, indicating largely separate modes of action. These observations suggest that the tidal muscle stretches that are attendant to spontaneous breathing comprise the first line of defense against bronchospasm and that tidal muscle stretches may be the most important of all known bronchodilating agencies.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
8750-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
90
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2306-10
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Relaxation of activated airway smooth muscle: relative potency of isoproterenol vs. tidal stretch.
pubmed:affiliation
Physiology Program, Harvard School of Public Health, Boston, Massachusetts 02130, USA.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro, Research Support, U.S. Gov't, P.H.S.