ABSTRACT
The great majority of research on blood coagulation is focused on events occurring within the vascular space involved in thrombosis and hemostasis. Comparatively little work is directed toward the interaction of the various components of coagulation present in the interstitial space. It is acknowledged that perivascular components, such as tissue factor, fall into a gray area in having a role in vascular hemostasis and in the interstitial space. In the past two decades, there has been an increased interest in the possible role of coagulation proteins in interstitial fibrosis and in the role of thrombin in the brain and other organs mediated through action on protease-activated receptors. 1 The following discussion will show that, with the exception of blood platelets, the various components of coagulation are present in the interstitial space.
