Increased sodium/calcium exchanger activity enhances beta-adrenergic-mediated increase in heart rate: Whole-heart study in a homozygous sodium/calcium exchanger overexpressor mouse model

This study is the first to demonstrate that increased NCX activity enhances beta-adrenergic increase of heart rate. Mechanistically, increased NCX inward mode activity may promote acceleration of diastolic depolarization in sinus nodal pacemaker cells, thus enhancing chronotropy in NCX-OE. These findings suggest a novel potential therapeutic target for heart rate control in the presence of increased NCX activity, such as heart failure.