I am pI eased to present to the readers the Proceedings of the Second International Congress on Myocardial and Cellular Bioenerge- tics and Compartmentation which was held in Los Angeles during February 16-18, 1984. I would I ike to express my deep appreciation to all those who have encouraged us to hold the Second International Congress. This endeavor could not have been possible without the generous finan- cial support of the following: The American Society for Magnesium Research, The University of Southern California Department of Con- tinuing Medical Education, Alpha Therapeutics, ALSEB Scientific Products, The American Physiological Society, Ciba-Geigy Corpora- tion, Victor Gura, M.D., Merck Sharp and Dohme, Phosphoenergetics, Stuart Pharmaceuticals, and the Upjohn Company. A note of special thanks goes to Samuel Bessman, M.D., who has been a source of constant support and encouragement for this Con- gress and for my research endeavors. Nachman Brautbar vii CONTENTS I. HICROCOMPARTHENTATION AND ENERGY TRANSPORT: The Physiological Significance of the Creatine Phosphate Shuttle . . . . . . . .. . . ........ .