How does thrombolytic therapy function to dissolve blood clots?

Thrombolytic therapy works by mimicking an endogenous substance, specifically tissue plasminogen activator (tPA), which is a natural protein in the body that helps dissolve blood clots. When a thrombolytic agent is administered, it activates plasminogen, converting it into plasmin, the enzyme responsible for breaking down fibrin, the main component of blood clots. This process effectively dissolves the clot and restores blood flow in areas affected by the obstruction, such as during a heart attack or stroke.

This mechanism distinguishes thrombolytic agents from other treatments that may either promote clot formation or increase the activity of platelets, which does not address the existing clots directly. Likewise, while enhancing blood coagulation or decreasing vascular tone might influence overall hemostasis, they do not directly contribute to the breakdown of established thrombi as thrombolytics do.