Excitation-contraction coupling

Definition

Excitation-contraction coupling is the physiological process by which an electrical stimulus leads to muscle contraction. It bridges the gap between the generation of an action potential in a muscle fiber and the onset of contraction.

Related terms

Action potential: A rapid rise and subsequent fall in voltage or membrane potential across a cellular membrane.

Sarcoplasmic reticulum: A specialized type of smooth endoplasmic reticulum that regulates calcium ion concentration in the cytoplasm of striated muscle cells.

Cross: bridge cycle - The process during muscle contraction where myosin heads bind to actin, undergo a power stroke, and then detach from actin, leading to muscle shortening