kardiomyocyte

A cardiomyocyte is a muscle cell found in the heart, also known as a cardiac myocyte. These specialized cells are responsible for the heart's ability to contract and pump blood throughout the body. Cardiomyocytes are distinct from skeletal muscle cells and smooth muscle cells due to their unique structure and function.

Structurally, cardiomyocytes are elongated and branched cells. They contain myofibrils, which are the contractile units of the muscle cell, composed of actin and myosin filaments. A key feature of cardiomyocytes is the presence of intercalated discs. These specialized junctions connect adjacent cardiomyocytes, allowing for rapid and coordinated electrical and mechanical coupling. Intercalated discs contain gap junctions, which facilitate the passage of ions, and desmosomes, which provide strong mechanical adhesion, preventing the cells from pulling apart during contraction.

The primary function of cardiomyocytes is to generate and transmit electrical impulses that trigger rhythmic contractions of the heart. These contractions create the pumping action necessary for circulation. Cardiomyocytes have a high metabolic rate and rely heavily on aerobic respiration for energy production, which is supplied by a large number of mitochondria within the cell.

Damage to cardiomyocytes, such as that caused by a heart attack or certain diseases, can lead to impaired heart function and can contribute to conditions like heart failure. Research into cardiomyocyte regeneration and repair is an active area of study.