Szívizomsejté

Szívizomsejté, also known as a cardiomyocyte, is the specialized cell type that makes up the muscle tissue of the heart. These cells are unique in their structure and function, enabling the heart to contract rhythmically and pump blood throughout the body. Cardiomyocytes are characterized by their striated appearance, similar to skeletal muscle cells, due to the organized arrangement of contractile proteins called actin and myosin. However, unlike skeletal muscle, cardiomyocytes are involuntary, meaning their contraction is not under conscious control.

A key feature of cardiomyocytes is their interconnectedness. They are linked together by specialized junctions called intercalated discs. These discs contain gap junctions, which allow electrical signals to pass rapidly from one cell to another, facilitating synchronized contraction of the entire heart muscle. Cardiomyocytes also possess a high density of mitochondria, the powerhouses of the cell, reflecting the heart's constant and demanding energy requirements.

The electrical activity of cardiomyocytes is crucial for the coordinated pumping action of the heart. Specialized pacemaker cells within the heart initiate electrical impulses that spread through the cardiomyocytes, triggering a wave of contraction. This process is regulated by various ion channels and neurotransmitters. Damage to cardiomyocytes, such as that occurring during a heart attack, can impair the heart's ability to pump effectively and can lead to serious health consequences. The study of cardiomyocytes is fundamental to understanding cardiac physiology and developing treatments for cardiovascular diseases.