Aprotinin

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  Aprotinin
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Aprotinin

Aprotinin is a serine protease inhibitor derived from bovine lung tissue. It is used in medicine to reduce bleeding during complex surgeries, such as cardiac surgery. Aprotinin works by inhibiting several proteolytic enzymes, including trypsin, plasmin, and kallikrein.

Mechanism of Action

Aprotinin functions by forming reversible stoichiometric complexes with proteases, thereby inhibiting their activity. This inhibition is particularly effective against plasmin, an enzyme involved in the breakdown of fibrin, which is a key component of blood clots. By inhibiting plasmin, aprotinin helps to maintain clot stability and reduce bleeding.

Clinical Uses

Aprotinin has been primarily used in cardiopulmonary bypass surgeries to reduce perioperative blood loss and the need for blood transfusions. It has also been used in other surgical procedures where significant bleeding is anticipated.

Safety and Efficacy

The use of aprotinin has been controversial due to concerns about its safety profile. Some studies have suggested an increased risk of renal failure, myocardial infarction, and stroke associated with its use. As a result, aprotinin was temporarily withdrawn from the market in some countries but has since been reintroduced with specific guidelines and restrictions.

Pharmacokinetics

Aprotinin is administered intravenously and has a rapid onset of action. It is distributed in the extracellular space and is primarily eliminated by the kidneys. The half-life of aprotinin is approximately 150 minutes, but this can vary depending on the patient's renal function.

History

Aprotinin was first isolated in the 1930s and was introduced into clinical practice in the 1960s. It gained widespread use in the 1980s and 1990s for its ability to reduce bleeding during surgery. However, its use declined in the late 2000s due to safety concerns, leading to a reevaluation of its risk-benefit profile.

Related Pages

• Protease inhibitor
• Cardiac surgery
• Fibrinolysis
• Hemostasis