verihiutymät

Verihiutymät, also known as platelets or thrombocytes, are small, irregular-shaped blood cells that play a crucial role in hemostasis, the process of stopping bleeding. They are produced in the bone marrow from megakaryocytes, large cells that fragment into thousands of these tiny components.

When a blood vessel is injured, platelets are activated. They adhere to the site of injury and aggregate, forming a plug that helps to seal the damaged area. This process is facilitated by a cascade of chemical signals, involving various proteins and clotting factors. Platelets also release substances that promote blood clotting, further strengthening the plug and preventing excessive blood loss.

The normal platelet count in adults ranges from 150,000 to 400,000 per microliter of blood. A low platelet count, known as thrombocytopenia, can increase the risk of bleeding. Conversely, a high platelet count, called thrombocytosis, can lead to an increased risk of blood clots. Disorders affecting platelet function, such as von Willebrand disease or Bernard-Soulier syndrome, can also impair the body's ability to control bleeding.

Platelets have a lifespan of about 7 to 10 days and are continuously replenished by the bone marrow. Their examination is a common part of a complete blood count (CBC) and provides valuable information about a person's overall health, particularly regarding bleeding and clotting disorders.