Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5 Pt 1
pubmed:dateCreated
1998-7-1
pubmed:abstractText
Direct action of the cardiotonic bipyridine milrinone on the cross bridges of single fibers of skinned rabbit skeletal muscle was investigated. At 10 degrees C and pH 7.0, milrinone reduced isometric tension in a logarithmically concentration-dependent manner, with a 55% reduction in force at 0.6 mM. Milrinone also reduced Ca2+ sensitivity of skinned fibers in terms of force production; the shift in the force-pCa curve indicated a change in the pCa value at 50% maximal force from 6.10 to 5.94. The unloaded velocity of shortening was reduced by 18% in the presence of 0.6 mM milrinone. Parts of the transient tension response to step change in length were altered by milrinone, so that the test and control transients could not be superimposed. The results indicate that milrinone interferes with the cross-bridge cycle and possibly detains cross bridges in low-force states. The results also suggest that the positive inotropic effect of milrinone on cardiac muscle is probably not due to the drug's direct action on the muscle cross bridges. The specific and reversible action of the bipyridine on muscle cross bridges makes it a potentially useful tool for probing the chemomechanical cross-bridge cycle.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
274
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C1306-11
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Milrinone inhibits contractility in skinned skeletal muscle fibers.
pubmed:affiliation
Department of Anatomy, University of British Columbia, Vancouver, Canada.
pubmed:publicationType
Journal Article