Heart attacks are usually caused by a blood clot blocking an artery supplying blood to the heart. Current treatments are designed at relieving this blockage as quickly as possible to minimise damage to the heart muscle. However in restoring the supply of blood local damage known as "ischaemia-reperfusion injury" may occur. The aim of this study is to assess how clot forming and clot dissolving pathways are affected during this process, and examine the role of a natural inflammatory hormone, bradykinin. This will help us to understand the mechanism by which ischaemia-reperfusion injury may occur and to devise new treatments for heart attacks.