Tissue plasminogen activator (tPA) is a protein involved in the breakdown of blood clots. It is produced naturally in the body and plays a crucial role in the process of fibrinolysis, which helps to dissolve clots that can obstruct blood flow. tPA converts plasminogen, an inactive protein, into plasmin, the active enzyme that breaks down fibrin, the main component of blood clots. In medical settings, tPA is used as a treatment for certain types of strokes, specifically ischemic strokes, where a clot blocks blood flow to the brain. Administering tPA can help restore blood flow and minimize brain damage if given within a specific time frame after the onset of symptoms.