Myosin-binding protein C phosphorylation, myofibril structure, and contractile function during low-flow ischemia

Article

关键词: TROPONIN-I PROTEOLYSIS;    STUNNED MYOCARDIUM;    MUSCLE;    DEGRADATION;    HEART;    CA2+;   

DOI  :  10.1161/01.CIR.0000155609.95618.75

来源: SCIE

【 摘 要 】

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 and Results - 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.

【 授权许可】

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