Ablation of phospholamban rescues reperfusion arrhythmias but exacerbates myocardium infarction in hearts with Ca2+/calmodulin kinase II constitutive phosphorylation of ryanodine receptors
Abstract
Abnormal Ca2+ release from the sarcoplasmic reticulum (SR), associated with Ca2+-calmodulin kinase II (CaMKII)-dependent phosphorylation of RyR2 at Ser2814, has consistently been linked to arrhythmogenesis and ischaemia/reperfusion (I/R)-induced cell death. In contrast, the role played by SR Ca2+ uptake under these stress conditions remains controversial. We tested the hypothesis that an increase in SR Ca2+ uptake is able to attenuate reperfusion arrhythmias and cardiac injury elicited by increased RyR2-Ser2814 phosphorylation. We used WT mice, which have been previously shown to exhibit a transient increase in RyR2-Ser2814 phosphorylation at the onset of reperfusion; mice with constitutive pseudo-phosphorylation of RyR2 at Ser2814 (S2814D) to exacerbate CaMKII-dependent reperfusion arrhythmias and cardiac damage, and phospholamban (PLN)-deficient-S2814D knock-in (SDKO) mice resulting from crossbreeding S2814D with phospholamban knockout deficient (PLNKO) mice. At baseline, S2814D and SDKO mice had structurally normal hearts. Moreover none of the strains were arrhythmic before ischaemia. Upon cardiac I/R, WT, and S2814D hearts exhibited abundant arrhythmias that were prevented by PLN ablation. In contrast, PLN ablation increase...Continue Reading
References
Ca2+/calmodulin-dependent protein kinase II phosphorylation regulates the cardiac ryanodine receptor
Reduced SERCA2 abundance decreases the propensity for Ca2+ wave development in ventricular myocytes.
The signalling pathway of CaMKII-mediated apoptosis and necrosis in the ischemia/reperfusion injury.
Citations
Related Concepts
Related Feeds
Cardiotoxicity
Cardiotoxicity refers to the muscle damage or dysfunction of heart electrophysiology caused by drug intake or due to disease complications. It is a well-known side effect of several cytotoxic drugs, especially of the anthracyclines and can lead to long term morbidity. Here is the latest research.
Atrial Fibrillation
Atrial fibrillation is a common arrhythmia that is associated with substantial morbidity and mortality, particularly due to stroke and thromboembolism. Here is the latest research.
Arrhythmia
Arrhythmias are abnormalities in heart rhythms, which can be either too fast or too slow. They can result from abnormalities of the initiation of an impulse or impulse conduction or a combination of both. Here is the latest research on arrhythmias.