During the last decade we have witnessed a rapid expansion of our knowledge of the role of the endothelium in the control of vascular tone and hemostasis. In paricular, developments in molecular biology have enabled us to understand its physiology in greater detail. Furthermore, it is now clear that dysfunction of the endothelium contributes to various cardiovascular diseases. This is especially true for the coronary vascular bed. Development of atherosclerosis, disturbed vasomotor tone in stable ischemic syndromes, and the interaction of thrombocytes with the endothelium in acute ischemic...