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 maintain normal blood flow. tPA converts plasminogen, an inactive protein, into plasmin, the active enzyme that dissolves clots. In medical settings, tPA is used as a treatment for certain types of strokes, specifically ischemic strokes, where a blood 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.