Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2004-2-18
pubmed:abstractText
Two smooth muscle myosin heavy chain isoforms that differ by the presence ([+]insert) or the absence ([-]insert) of a 7-amino acid insert in the motor domain have a 2-fold difference in their in vitro actin filament velocity. We hypothesized that a preferential expression of the fast (+)insert isoform in airway smooth muscle would increase the rate of bronchoconstriction. To verify our hypothesis we measured the time course of bronchoconstriction following a bolus injection of methacholine (160 microg/kg) in (+)insert isoform knockout (KO) and corresponding wild-type (WT) mice. Neither baseline airway resistance (Raw) (0.424 +/- 0.04 for WT and 0.374 +/- 0.01 cm H(2)O.s.ml(-1) for KO) nor peak Raw (4.1 +/- 0.9 for WT and 4.0 +/- 0.5 cm H(2)O.s.ml(-1) for KO) differed between groups. However, the time to peak Raw was significantly longer in the KO (17.2 +/- 0.6 s) compared with the WT (14.6 +/- 0.8 s) mice (P < 0.05). Differentiating Raw with respect to time revealed a greater rate of bronchoconstriction for the WT during the initial 4 s, presumably reflecting the faster shortening velocities under these relatively unloaded conditions. Reverse transcriptase-polymerase chain reaction analysis revealed that the (+)insert myosin isoform mRNA content in the WT airways was 47.8 +/- 5.6%. We conclude that the presence of the (+)insert myosin isoform in the airways increases the rate of bronchoconstriction.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1044-1549
pubmed:author
pubmed:issnType
Print
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
326-32
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Time course of airway mechanics of the (+)insert myosin isoform knockout mouse.
pubmed:affiliation
Meakins Christie Laboratories, Department of Medicine, McGill University, 3626 St-Urbain St., Montréal, PQ, H2X 2P2 Canada.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't