Unlike the action potential in skeletal muscle cells, the cardiac action potential is not initiated by nervous activity. Instead, it arises from a group of specialized cells known as pacemaker cells, that have …

The top image is a graph depicting the action potential of a cardiac myocyte plotted against membrane potential and time. The action potential phases are clearly illustrated to emphasize the process that …

Cardiac action potential (AP) is defined as a small voltage change (approximately 0.1 V) that initiates the contraction of cardiac myocytes, enabling the orderly spread of electrical excitation and subsequent …

Aug 23, 2025 · This diagram compares the cardiac muscle action potential and skeletal muscle action potential, highlighting variations in duration, ion involvement, and refractory periods that support the …

Jun 8, 2025 · This article looks at how action potentials spread in ventricular cells, their shape and modulation in disease states.

Phase 4 of the action potential in the sinoatrial node is called “pacemaker potential”, because it is responsible for the spontaneous repetitive depolarization. The depolarization spreads from the …

There are three general types of cardiac action potentials that are distinguished, in part, by the presence or absence of spontaneous pacemaker activity and by how rapidly they depolarize.

Describe the different phases of the cardiac action potential and their significance. The cardiac action potential consists of several distinct phases: rapid depolarization, a plateau phase, and repolarization.

Sep 20, 2025 · In cardiac muscle cells, also known as cardiomyocytes, the resting membrane potential is approximately -90 mV. For an action potential to occur, this membrane potential must be …

In summary, while skeletal muscle action potentials rely primarily on sodium and potassium ions, cardiac muscle action potentials involve sodium, calcium, and potassium ions.