Kinetic Processes Specific to Platelets.
- Adhesion – When platelets adhere to exposed collagen, they take on a characteristic “spiny” shape. Their inherent stickiness, and the aforementioned spiny shape serve to compliment each other during this process. Von Willebrands Factor (vWF) is absorbed by surface receptors on both the platelet and exposed subendothelial tissue, thereby linking the platelets to the tissue.
- Release – This process occurs prior to aggregation. Platelets dump the contents of their granules (ADP, Serotonin, & Calcium), which aids the upcoming aggregation process by acting as a chemical signal.
- Aggregation – Platelets physically bind to each other, not just to the exposed subendothelial walls and collagen of the breached vessel. Platelet aggregation requires sufficient chemical signal stimulation.
- Stabilization (technically part of secondary hemostasis as fibrin is a product of secondary hemostasis)– This process strengthens the platelet plug with the addition of interwoven fibrin strands, ultimately producing a fibrin clot. The durable fibrin clot is the ultimate goal of hemostatic processes.
