Cardiovascular Physiology: Cellular and Molecular Regulation

Abstract In a normal human life span, the heart beats billions of times. Each beat represents a remarkable combination of events working in harmony over milliseconds to propel blood into the vasculature for distribution to tissues of the body. This chapter first reviews the electrical, biochemical, and mechanical events that constitute a heart beat. Particular emphasis is placed upon intrinsic and extrinsic regulation of these processes in order to highlight how each can be affected by drugs or disease. The chapter then discusses how the pulsatile forces generated by myocardial excitation and contraction move blood into and through the circulation. A wide range of factors influencing how different vessels along the vascular tree contract or relax in order to effectively disperse the pressure and flow generated during systole and diastole are reviewed. Finally, potential implications of recent technological advances in defining subcellular and molecular aspects of cardiovascular physiology are described.