Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1987-2-12
pubmed:abstractText
Myosin light chain phosphorylation in intact rat thoracic aorta was elevated during contraction induced by 0.3 microM norepinephrine, but was not maintained. Addition of 0.5 microM sodium nitroprusside to norepinephrine treated rat aorta strips led to elevation of cyclic GMP levels, relaxation of tension, and dephosphorylation of myosin light chain. Depletion of extracellular calcium or addition of calmodulin antagonists trifluoperazine and W7 diminished the contraction and phosphorylation of myosin light chain by norepinephrine, but did not prevent dephosphorylation by sodium nitroprusside or the elevated levels of cyclic GMP. Isoproterenol, 8-bromo cyclic GMP, and dibutyryl cyclic AMP all caused dephosphorylation of myosin light chain and induced relaxation during the period of development of tone. Eight other proteins had increased phosphorylation following norepinephrine treatment and one protein had less phosphorylation. The different proteins phosphorylated by norepinephrine showed varying degrees of sensitivity to Ca2+-free solution and to the calmodulin antagonists. The pattern of protein phosphorylation caused by sodium nitroprusside was best mimicked by 8-bromo cyclic GMP, rather than isoproterenol and dibutyryl cyclic AMP. These proteins were, generally, unaffected by Ca2+-free solution and the calmodulin antagonists. The present observations support the hypothesis that vasodilators inhibit tone development through myosin light chain dephosphorylation. Furthermore, the nitrovasodilators act through elevation of cyclic GMP and phosphorylation of proteins by cyclic GMP-dependent protein kinase.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0020-711X
pubmed:author
pubmed:issnType
Print
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
917-28
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Myosin light chain phosphorylation in contraction and relaxation of intact rat thoracic aorta.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't