a·pro·ti·nin (ā-prōt'n-ĭn, ā-prōt'-) n. A natural polypeptide and protease inhibitor that affects blood clotting and is used during high-risk surgery, such as cardiopulmonary bypass, to reduce bleeding.
Main Entry: apro·ti·nin Pronunciation: A-'prOt-&-nin Function: noun : a polypeptide used for its protease-inhibiting properties especiallyin the treatment of pancreatitis —see TRASYLOL