Intracellular calcium modulation of voltage-gated sodium channels in ventricular myocytes

摘要

Aims Cardiac voltage-gated sodium channels control action potential (AP) upstroke and cell excitability. Intracellular calcium (Ca_i2+) regulates AP properties by modulating various ion channels. Whether Ca_i2+ modulates sodium channels in ventricular myocytes is unresolved. We studied whether Ca_i2+ modulates sodium channels in ventricular myocytes at Ca_i2+ concentrations ([Ca_i2+]) present during the cardiac AP (0–500 nM), and how this modulation affects sodium channel properties in heart failure (HF), a condition in which Ca_i2+ homeostasis is disturbed.