R. Jacob - Böcker

Symposium, Munich, October 26-29, 1983

Cardiac hypertrophy and accompanying phenomena have received increasing attention in recent years - particularly in the basic sciences. The present volume contains the proceedings of the Erwin RIESCH SYMPOSIUM on "CARDIAC ADAPTATION TO HEMODYNAMIC OVERLOAD, TRAINING AND STRESS" held in Tiibingen on Sep­ tember 19-22, 1982. In addition to the topics of the previous symposia (1976 and 1979) concerned with problems of cardiac hypertrophy, the scope of this sequel meeting has been expanded to include related fields. The intention was to consider numerous related features and problems of chronic reactions of the heart (and vascular system) to abnormal hemodynamic loading, as well as alterations due to maturation, aging, training, neuroendocrine status and stress. Special attention has been paid to cardiac reactions at the level of contractile proteins. The results are considered primarily in light of long-term adaptation of the heart. Of course, research at the forefront of current knowledge need not always lead to congruent conclusions. Neither can the individual contributions always agree with the viewpoint of the editors. However, the broad array of individual approaches employed by biochemists, biolo­ gists, pathologists, physiologists, pharmacologists and clinical cardio­ logists will certainly help to provide a more balanced interpretation of the results in individual fields, stimulate reexamination of established con­ cepts and provide direction for future research.

Assessment of cardiac energetics at the level of ATP-synthesis, chemomechanical energy transformation and whole organ dynamics as a function of haemodynamic load, ventricular configuration and oxygen- and substrates supply is basic to understanding cardiac function under physiological and pathophysiological (hypertrophy, hypoxia, ischaemia and heart failure) conditions. Moreover, cardiac energetics should be an important consideration in the choice and application of drugs especially in the case of vasodilators, inotropic agents and in cardioprotective measures. Only by considering energetics at the subcellular, cellular, and whole-heart level we can arrive at a better understanding of cardiac performance and ultimately better clinical judgement and drug therapy. Quantification of myocardial energetics will also help to determine the optimal time for surgical interventions such as valvular replacement or aneurysm resection. The present volume is the outcome of an international symposium on cardiac energetics held in Gargellen/Montafon (Austria), June 1986. The contributions will certainly help bridge the existing gap between basic research involving isolated structures and that involving the whole organ, on the one hand, and render the results derived from basic research applicable to clinical problems, on the other hand.

The past years have witnessed considerable progress in the field of fundamental research in cardiology. Nevertheless, numerous problems and controversial concepts remain. Some of these controversies concern relatively simple issues, e. g. the question of the extent to which a common length-tension or pressure-volume relationship exists independent of type of contraction and preload. The present volume is a compendium of an Erwin Riesch sympo- sium held July 12-13,1985, with the aim of critically analysing generally accepted concepts and theories as well as current trends in cardiology. In common with previous Erwin Riesch symposia, priority was given to issues concerning chronic reactions of the heart, although basic principles of normal myocardial contraction and ventricular dynamics as well as clinical aspects were also discussed. We are greatly indebted to the Erwin Riesch-Stiftung for the invaluable generosity which enabled us to hold the symposium. R.Jacob VII Contents Foreword ...V I. Contractile elementary processes: Cross-bridge theory and excitation-contraction coupling The cross-bridge cycle in muscle.Mechanical, biochemical, and structural studies on single skinned rabbit psoas fibers to characterize cross-bridge kinetics in muscle for correlation with the actomyosin-ATPase in solution Brenner, B ...Calcium sensitivity of myofilaments in cardiac muscle - effect of myosin phosphorylation Morano, I. and J. C. Ruegg...17 Ca-pools involved in the regulation of cardiac contraction under positive inotropy. X-ray microanalysis on rapidly-frozen ventricular muscles of guinea-pig Wendt -Gallitelli, Maria F...25 The contribution of Na channel block to the negative inotropic effect of antiarrhythmic drugs Honerjiiger, P...