Spontaneous depolarization

Definition

Spontaneous depolarization is the automatic and gradual change in membrane potential that occurs in certain cardiac muscle cells, leading them to reach the threshold potential and generate an action potential without external stimulation. It is crucial for initiating and regulating the heart's rhythm.

Related terms

Action Potential:

A rapid change in membrane potential that travels along an excitable cell, such as a neuron or muscle cell, as a wave of electrical discharge.

Threshold Potential:

The critical level to which a membrane potential must be depolarized to initiate an action potential.

Pacemaker Cells:

Specialized cardiac cells that control the heart’s rhythms by generating and conducting regular electrical impulses through spontaneous depolarization