Cardiac Action Potential & Pacemaker — Practice
A physiologist records from a cardiac sinoatrial node cell. The slow diastolic depolarisation (pacemaker potential) that drives automaticity is principally carried by which current?
AThe delayed rectifier potassium current
BThe funny current (If) carried mainly by sodium through HCN channels
CThe L-type calcium current alone
DThe fast inward sodium current through voltage-gated Na+ channels