The role of spatial organization of Ca²⁺ release sites in the generation of arrhythmogenic diastolic Ca²⁺ release in myocytes from failing hearts.

ABSTRACT: In heart failure (HF), dysregulated cardiac ryanodine receptors (RyR2) contribute to the generation of diastolic Ca²⁺ waves (DCWs), thereby predisposing adrenergically stressed failing hearts to life-threatening arrhythmias. However, the specific cellular, subcellular, and molecular defects that account for cardiac arrhythmia in HF remain to be elucidated. Patch-clamp techniques and confocal Ca²⁺ imaging were applied to study spatially defined Ca²⁺ handling in ventricular myocytes isolated from normal (control) and failing canine hearts. Based on their activation time upon electrical stimulation, Ca²⁺ release sites were categorized as coupled, located in close proximity to the sarcolemmal Ca²⁺ channels, and uncoupled, the Ca²⁺

SUBMITTER: Belevych AE 

PROVIDER: S-EPMC5796415 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature