Review of Medical Physiology - William F. Ganong 2002

Physiology of Nerve and Muscle Cells
Excitable Tissue: Muscle
Cardiac Muscle (Myocardium) - Pacemaker Tissue

The Heart continues to contract even after all its nerves are severed and even if it is cut into pieces. This phenomenon is explained by the presence of specialized pacemaker tissue within the heart, which is capable of generating action potentials. The pacemaker tissue forms the heart's conduction system, which normally transmits impulses to all its chambers. It features an unstable Membrane Potential that slowly declines after each impulse until a certain threshold is reached, triggering the next impulse (see Chapter 28).



Last update: 10/08/2026

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