NaV1.5 is found primarily in cardiac muscle, where it mediates the fast influx of Na+-ions (INa) across the cell membrane, resulting in the fast depolarization phase of the cardiac action potential. As such, it plays a major role in impulse propagation through the heart.
NaV1.5 is primarily found in cardiac muscle cells and is responsible for rapidly bringing sodium ions (Na+) into the cell, which triggers the rapid depolarization phase of the heart's electrical signal. This action is crucial for transmitting impulses throughout the heart.