Myosin-binding protein C phosphorylation, myofibril structure, and contractile function during low-flow ischemia.
Circulation
; 111(7): 906-12, 2005 Feb 22.
Article
in En
| MEDLINE
| ID: mdl-15699252
ABSTRACT
BACKGROUND:
Contractile dysfunction develops in the chronically instrumented canine myocardium after bouts of low-flow ischemia and persists after reperfusion. The objective of this study is to identify whether changes in the phosphorylation state of myosin-binding protein C (MyBP-C) are a potential cause of dysfunction. METHODS ANDRESULTS:
During low-flow ischemia, MyBP-C is dephosphorylated, and the number of actomyosin cross-bridges in the central core of the sarcomere decreases as thick filaments dissemble from the periphery of the myofibril. During reperfusion, MyBP-C remains dephosphorylated, and its degradation is accelerated.CONCLUSIONS:
Dephosphorylation of MyBP-C may initiate changes in myofibril thick filament structure that decrease the interaction of myosin heads with actin thin filaments. Limiting the formation of actomyosin cross-bridges may contribute to the contractile dysfunction that is apparent after low-flow ischemia. Breakdown of MyBP-C during reperfusion may prolong myocardial stunning.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Carrier Proteins
/
Myocardial Ischemia
/
Myocardial Contraction
/
Myofibrils
Type of study:
Etiology_studies
Limits:
Animals
Language:
En
Journal:
Circulation
Year:
2005
Document type:
Article
Affiliation country:
Publication country:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
/
US
/
USA