vérlemez

Vérlemez, also known as a platelet or thrombocyte, is a small, irregular-shaped blood cell fragment that plays a crucial role in hemostasis, the process of stopping bleeding. These anucleated cell fragments are produced in the bone marrow from megakaryocytes, large cells that fragment into thousands of platelets.

When a blood vessel is injured, platelets are activated and aggregate at the site of injury. They release various substances, including clotting factors and proteins, that help to form a platelet plug. This plug acts as a temporary barrier, slowing down blood loss. Simultaneously, the released clotting factors initiate a cascade of reactions that ultimately leads to the formation of a fibrin clot, a more stable and durable plug that seals the damaged vessel.

Platelets also contribute to wound healing and immune responses. They can interact with other cells, release growth factors that promote tissue repair, and participate in inflammatory processes. The normal platelet count in a healthy adult typically ranges from 150,000 to 450,000 platelets per microliter of blood. A low platelet count, known as thrombocytopenia, can lead to excessive bleeding, while a high platelet count, or thrombocytosis, can increase the risk of blood clots.