1. Adenosine Receptor-Mediated Signal Transduction2. Adenosine Metabolism and Transport in the Mammalian Heart3. Cardiac Electrophysiology of Adenosine: Cellular Basis and Clinical Implications4. Protective Effects of Adenosine in Reversibly and Irreversibly Injured Ischemic Myocardium5. The Role of Adenosine in the Regulation of Cardiac Function: The Effect of Aging6. Direct and Indirect Effects of Extracellular ATP on Cardiac Myocytes