to the Endothelin System David M. Pollock ascular endothelial cells form a monolayer lining in all of the blood vessels of V the circulation. Initially, they were thought to function as a crude filter allow ing nutrients from the blood stream to diffuse through to the underlying tissues without letting proteins or blood cells escape. We now know that endothelial cells are important regulators of circulatory function, due in large measure to their rec ognized ability to synthesize and release many factors that regulate vascular smooth muscle tone. Endothelial-derived factors, including relaxing and contracting sub stances such as prostacyclin, nitric oxide (NO), and endothelin (ET), have been identified as important contributors in the regulation of vascular tone. Endothe lial cells have a highly active metabolic function and are involved in clearing a number of agents from circulating blood. In addition, they have the enzyme that inactivates bradykinin and converts angiotensin I into the very potent pressor agent, angiotensin II (Ang II). Endothelial cells also generate various proteins like von Willebrand's factor, tissue plasminogen activator, growth promoting factors and lipids such as platelet activating factor. It is now clear that in addition to the regu lation of vascular tone and hemodynamics, endothelial cells playa critical role in regulating growth and proliferative processes, inflammation and hemostasis.

1. Introduction to the Endothelin System

2. Endothelin Receptors and Receptor Antagonists
3. Novel Endothelin Receptors
4. "Sticky" Conundrums in the Endothelin System: Unique Binding Characteristics of Receptor Agonists and Antagonists
5. Functional Coordination and Cooperation Between Endothelin and Nitric Oxide Systems in Vascular Regulation
6. Molecular and Structural Biology of Endothelin Receptors
7. Cytokine Regulation of Endothelin Action
8. Endothelin Modulation of Renal Sodium and Water Transport
9. Endothelin and Ion Channels
10. Endothelin and Calcium Signaling
11. Endothelin Regulation of Cardiac Contractility: Signal Transduction Pathways
12. Endothelin Signaling to the Nucleus: Regulation of Gene Expression and Phenotype
13. Mechanisms of Endothelin-induced Mitogenesis and Activation of Stress Response Protein Kinases
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