Streptokinase and tPA share which mechanism of action?

Streptokinase and tissue plasminogen activator (tPA) both function by converting plasminogen to plasmin, which is the active form of the enzyme that dissolves fibrin clots. This process is crucial in the management of conditions such as myocardial infarction and pulmonary embolism, where the goal is to rapidly restore blood flow by breaking down the thrombus.

Streptokinase, a protein derived from streptococci bacteria, binds to plasminogen and forms a complex that activates it to plasmin. Similarly, tPA, which is produced by endothelial cells, binds to fibrin in the clot and converts nearby plasminogen to plasmin in a localized manner, enhancing fibrinolysis at the site of the thrombus. Both agents work by promoting clot breakdown, which is the shared mechanism of action that is critical in acute thrombotic events.

Other choices suggest different mechanisms, such as inhibition of thromboxane synthesis or blocking ADP receptors, which are not actions associated with either streptokinase or tPA.